diff --git a/mlprec/mld_caggr_bld.f90 b/mlprec/mld_caggr_bld.f90
new file mode 100644
index 00000000..41269806
--- /dev/null
+++ b/mlprec/mld_caggr_bld.f90
@@ -0,0 +1,153 @@
+!!$ 
+!!$ 
+!!$                           MLD2P4  version 1.0
+!!$  MultiLevel Domain Decomposition Parallel Preconditioners Package
+!!$             based on PSBLAS (Parallel Sparse BLAS version 2.2)
+!!$  
+!!$  (C) Copyright 2008
+!!$
+!!$                      Salvatore Filippone  University of Rome Tor Vergata       
+!!$                      Alfredo Buttari      University of Rome Tor Vergata
+!!$                      Pasqua D'Ambra       ICAR-CNR, Naples
+!!$                      Daniela di Serafino  Second University of Naples
+!!$ 
+!!$  Redistribution and use in source and binary forms, with or without
+!!$  modification, are permitted provided that the following conditions
+!!$  are met:
+!!$    1. Redistributions of source code must retain the above copyright
+!!$       notice, this list of conditions and the following disclaimer.
+!!$    2. Redistributions in binary form must reproduce the above copyright
+!!$       notice, this list of conditions, and the following disclaimer in the
+!!$       documentation and/or other materials provided with the distribution.
+!!$    3. The name of the MLD2P4 group or the names of its contributors may
+!!$       not be used to endorse or promote products derived from this
+!!$       software without specific written permission.
+!!$ 
+!!$  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+!!$  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+!!$  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+!!$  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE MLD2P4 GROUP OR ITS CONTRIBUTORS
+!!$  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+!!$  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+!!$  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+!!$  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+!!$  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+!!$  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+!!$  POSSIBILITY OF SUCH DAMAGE.
+!!$ 
+!!$
+! File: mld_caggr_bld.f90
+!
+! Subroutine: mld_caggr_bld
+! Version:    complex
+!
+!  This routine builds the preconditioner corresponding to the current
+!  level of the multilevel preconditioner. The routine first builds the
+!  (coarse) matrix associated to the current level from the (fine) matrix
+!  associated to the previous level, then builds the related base preconditioner.
+!  Note that this routine is only ever called on levels >= 2. 
+!
+! 
+! Arguments:
+!    a       -  type(psb_dspmat_type).
+!               The sparse matrix structure containing the local part of the
+!               matrix to be preconditioned.
+!    desc_a  -  type(psb_desc_type), input.
+!               The communication descriptor of a.
+!    p       -  type(mld_c_onelev_type), input/output.
+!               The preconditioner data structure containing the local
+!               part of the one-level preconditioner to be built.
+!    info    -  integer, output.
+!               Error code.         
+!  
+subroutine mld_caggr_bld(a,desc_a,p,info)
+
+  use psb_base_mod
+  use mld_inner_mod, mld_protect_name => mld_caggr_bld
+
+  implicit none
+
+  ! Arguments
+  type(psb_cspmat_type), intent(in), target :: a
+  type(psb_desc_type), intent(in), target   :: desc_a
+  type(mld_c_interlev_prec_type), intent(inout),target    :: p
+  integer, intent(out)                      :: info
+
+  ! Local variables
+  type(psb_desc_type)    :: desc_ac
+  type(psb_cspmat_type)  :: ac
+  character(len=20)      :: name
+  integer                :: ictxt, np, me, err_act
+
+  name='mld_caggr_bld'
+  if (psb_get_errstatus().ne.0) return 
+  call psb_erractionsave(err_act)
+  info = 0
+  ictxt = psb_cd_get_context(desc_a)
+  call psb_info(ictxt,me,np)
+
+  if (.not.allocated(p%iprcparm)) then 
+    info = 2222
+    call psb_errpush(info,name)
+    goto 9999
+  endif
+  call mld_check_def(p%iprcparm(mld_ml_type_),'Multilevel type',&
+       &   mld_mult_ml_,is_legal_ml_type)
+  call mld_check_def(p%iprcparm(mld_aggr_alg_),'Aggregation',&
+       &   mld_dec_aggr_,is_legal_ml_aggr_alg)
+  call mld_check_def(p%iprcparm(mld_aggr_kind_),'Smoother',&
+       &   mld_smooth_prol_,is_legal_ml_aggr_kind)
+  call mld_check_def(p%iprcparm(mld_coarse_mat_),'Coarse matrix',&
+       &   mld_distr_mat_,is_legal_ml_coarse_mat)
+  call mld_check_def(p%iprcparm(mld_smoother_pos_),'smooth_pos',&
+       &   mld_pre_smooth_,is_legal_ml_smooth_pos)
+  call mld_check_def(p%iprcparm(mld_aggr_omega_alg_),'Omega Alg.',&
+       &   mld_eig_est_,is_legal_ml_aggr_omega_alg)
+  call mld_check_def(p%iprcparm(mld_aggr_eig_),'Eigenvalue estimate',&
+       &   mld_max_norm_,is_legal_ml_aggr_eig)
+  call mld_check_def(p%rprcparm(mld_aggr_omega_val_),'Omega',szero,is_legal_s_omega)
+  call mld_check_def(p%rprcparm(mld_aggr_thresh_),'Aggr_Thresh',szero,is_legal_s_aggr_thrs)
+  
+
+  !
+  !  Build a mapping between the row indices of the fine-level matrix 
+  !  and the row indices of the coarse-level matrix, according to a decoupled 
+  !  aggregation algorithm. This also defines a tentative prolongator from
+  !  the coarse to the fine level.
+  ! 
+  call mld_aggrmap_bld(p%iprcparm(mld_aggr_alg_),p%rprcparm(mld_aggr_thresh_),&
+       & a,desc_a,p%nlaggr,p%mlia,info)
+  if(info /= 0) then
+    call psb_errpush(4010,name,a_err='mld_aggrmap_bld')
+    goto 9999
+  end if
+
+  !
+  ! Build the coarse-level matrix from the fine level one, starting from 
+  ! the mapping defined by mld_aggrmap_bld and applying the aggregation
+  ! algorithm specified by p%iprcparm(mld_aggr_kind_)
+  !
+  call mld_aggrmat_asb(a,desc_a,p,info)
+  if(info /= 0) then
+    call psb_errpush(4010,name,a_err='mld_aggrmat_asb')
+    goto 9999
+  end if
+  !
+  ! Fix the base_a and base_desc pointers for handling of residuals.
+  ! This is correct because this routine is only called at levels >=2.
+  !
+  p%base_a    => p%ac
+  p%base_desc => p%desc_ac
+  
+  call psb_erractionrestore(err_act)
+  return
+
+9999 continue
+  call psb_erractionrestore(err_act)
+  if (err_act.eq.psb_act_abort_) then
+    call psb_error()
+    return
+  end if
+  Return
+
+end subroutine mld_caggr_bld
diff --git a/mlprec/mld_daggr_bld.f90 b/mlprec/mld_daggr_bld.f90
new file mode 100644
index 00000000..3398ff0a
--- /dev/null
+++ b/mlprec/mld_daggr_bld.f90
@@ -0,0 +1,153 @@
+!!$ 
+!!$ 
+!!$                           MLD2P4  version 1.0
+!!$  MultiLevel Domain Decomposition Parallel Preconditioners Package
+!!$             based on PSBLAS (Parallel Sparse BLAS version 2.2)
+!!$  
+!!$  (C) Copyright 2008
+!!$
+!!$                      Salvatore Filippone  University of Rome Tor Vergata       
+!!$                      Alfredo Buttari      University of Rome Tor Vergata
+!!$                      Pasqua D'Ambra       ICAR-CNR, Naples
+!!$                      Daniela di Serafino  Second University of Naples
+!!$ 
+!!$  Redistribution and use in source and binary forms, with or without
+!!$  modification, are permitted provided that the following conditions
+!!$  are met:
+!!$    1. Redistributions of source code must retain the above copyright
+!!$       notice, this list of conditions and the following disclaimer.
+!!$    2. Redistributions in binary form must reproduce the above copyright
+!!$       notice, this list of conditions, and the following disclaimer in the
+!!$       documentation and/or other materials provided with the distribution.
+!!$    3. The name of the MLD2P4 group or the names of its contributors may
+!!$       not be used to endorse or promote products derived from this
+!!$       software without specific written permission.
+!!$ 
+!!$  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+!!$  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+!!$  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+!!$  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE MLD2P4 GROUP OR ITS CONTRIBUTORS
+!!$  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+!!$  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+!!$  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+!!$  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+!!$  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+!!$  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+!!$  POSSIBILITY OF SUCH DAMAGE.
+!!$ 
+!!$
+! File: mld_daggr_bld.f90
+!
+! Subroutine: mld_daggr_bld
+! Version:    real
+!
+!  This routine builds the preconditioner corresponding to the current
+!  level of the multilevel preconditioner. The routine first builds the
+!  (coarse) matrix associated to the current level from the (fine) matrix
+!  associated to the previous level, then builds the related base preconditioner.
+!  Note that this routine is only ever called on levels >= 2. 
+!
+! 
+! Arguments:
+!    a       -  type(psb_dspmat_type).
+!               The sparse matrix structure containing the local part of the
+!               matrix to be preconditioned.
+!    desc_a  -  type(psb_desc_type), input.
+!               The communication descriptor of a.
+!    p       -  type(mld_d_onelev_type), input/output.
+!               The preconditioner data structure containing the local
+!               part of the one-level preconditioner to be built.
+!    info    -  integer, output.
+!               Error code.         
+!  
+subroutine mld_daggr_bld(a,desc_a,p,info)
+
+  use psb_base_mod
+  use mld_inner_mod, mld_protect_name => mld_daggr_bld
+
+  implicit none
+
+  ! Arguments
+  type(psb_dspmat_type), intent(in), target :: a
+  type(psb_desc_type), intent(in), target   :: desc_a
+  type(mld_d_interlev_prec_type), intent(inout),target    :: p
+  integer, intent(out)                      :: info
+
+  ! Local variables
+  type(psb_desc_type)    :: desc_ac
+  type(psb_dspmat_type)  :: ac
+  character(len=20)      :: name
+  integer                :: ictxt, np, me, err_act
+
+  name='mld_daggr_bld'
+  if (psb_get_errstatus().ne.0) return 
+  call psb_erractionsave(err_act)
+  info = 0
+  ictxt = psb_cd_get_context(desc_a)
+  call psb_info(ictxt,me,np)
+
+  if (.not.allocated(p%iprcparm)) then 
+    info = 2222
+    call psb_errpush(info,name)
+    goto 9999
+  endif
+  call mld_check_def(p%iprcparm(mld_ml_type_),'Multilevel type',&
+       &   mld_mult_ml_,is_legal_ml_type)
+  call mld_check_def(p%iprcparm(mld_aggr_alg_),'Aggregation',&
+       &   mld_dec_aggr_,is_legal_ml_aggr_alg)
+  call mld_check_def(p%iprcparm(mld_aggr_kind_),'Smoother',&
+       &   mld_smooth_prol_,is_legal_ml_aggr_kind)
+  call mld_check_def(p%iprcparm(mld_coarse_mat_),'Coarse matrix',&
+       &   mld_distr_mat_,is_legal_ml_coarse_mat)
+  call mld_check_def(p%iprcparm(mld_smoother_pos_),'smooth_pos',&
+       &   mld_pre_smooth_,is_legal_ml_smooth_pos)
+  call mld_check_def(p%iprcparm(mld_aggr_omega_alg_),'Omega Alg.',&
+       &   mld_eig_est_,is_legal_ml_aggr_omega_alg)
+  call mld_check_def(p%iprcparm(mld_aggr_eig_),'Eigenvalue estimate',&
+       &   mld_max_norm_,is_legal_ml_aggr_eig)
+  call mld_check_def(p%rprcparm(mld_aggr_omega_val_),'Omega',dzero,is_legal_omega)
+  call mld_check_def(p%rprcparm(mld_aggr_thresh_),'Aggr_Thresh',dzero,is_legal_aggr_thrs)
+  
+
+  !
+  !  Build a mapping between the row indices of the fine-level matrix 
+  !  and the row indices of the coarse-level matrix, according to a decoupled 
+  !  aggregation algorithm. This also defines a tentative prolongator from
+  !  the coarse to the fine level.
+  ! 
+  call mld_aggrmap_bld(p%iprcparm(mld_aggr_alg_),p%rprcparm(mld_aggr_thresh_),&
+       & a,desc_a,p%nlaggr,p%mlia,info)
+  if(info /= 0) then
+    call psb_errpush(4010,name,a_err='mld_aggrmap_bld')
+    goto 9999
+  end if
+
+  !
+  ! Build the coarse-level matrix from the fine level one, starting from 
+  ! the mapping defined by mld_aggrmap_bld and applying the aggregation
+  ! algorithm specified by p%iprcparm(mld_aggr_kind_)
+  !
+  call mld_aggrmat_asb(a,desc_a,p,info)
+  if(info /= 0) then
+    call psb_errpush(4010,name,a_err='mld_aggrmat_asb')
+    goto 9999
+  end if
+  !
+  ! Fix the base_a and base_desc pointers for handling of residuals.
+  ! This is correct because this routine is only called at levels >=2.
+  !
+  p%base_a    => p%ac
+  p%base_desc => p%desc_ac
+  
+  call psb_erractionrestore(err_act)
+  return
+
+9999 continue
+  call psb_erractionrestore(err_act)
+  if (err_act.eq.psb_act_abort_) then
+    call psb_error()
+    return
+  end if
+  Return
+
+end subroutine mld_daggr_bld
diff --git a/mlprec/mld_saggr_bld.f90 b/mlprec/mld_saggr_bld.f90
new file mode 100644
index 00000000..942f4b97
--- /dev/null
+++ b/mlprec/mld_saggr_bld.f90
@@ -0,0 +1,148 @@
+!!$ 
+!!$ 
+!!$                           MLD2P4  version 1.0
+!!$  MultiLevel Domain Decomposition Parallel Preconditioners Package
+!!$             based on PSBLAS (Parallel Sparse BLAS version 2.2)
+!!$  
+!!$  (C) Copyright 2008
+!!$
+!!$                      Salvatore Filippone  University of Rome Tor Vergata       
+!!$                      Alfredo Buttari      University of Rome Tor Vergata
+!!$                      Pasqua D'Ambra       ICAR-CNR, Naples
+!!$                      Daniela di Serafino  Second University of Naples
+!!$ 
+!!$  Redistribution and use in source and binary forms, with or without
+!!$  modification, are permitted provided that the following conditions
+!!$  are met:
+!!$    1. Redistributions of source code must retain the above copyright
+!!$       notice, this list of conditions and the following disclaimer.
+!!$    2. Redistributions in binary form must reproduce the above copyright
+!!$       notice, this list of conditions, and the following disclaimer in the
+!!$       documentation and/or other materials provided with the distribution.
+!!$    3. The name of the MLD2P4 group or the names of its contributors may
+!!$       not be used to endorse or promote products derived from this
+!!$       software without specific written permission.
+!!$ 
+!!$  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+!!$  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+!!$  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+!!$  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE MLD2P4 GROUP OR ITS CONTRIBUTORS
+!!$  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+!!$  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+!!$  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+!!$  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+!!$  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+!!$  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+!!$  POSSIBILITY OF SUCH DAMAGE.
+!!$ 
+!!$
+! File: mld_saggr_bld.f90
+!
+! Subroutine: mld_saggr_bld
+! Version:    real
+!
+!  This routine builds the preconditioner corresponding to the current
+!  level of the multilevel preconditioner. The routine first builds the
+!  (coarse) matrix associated to the current level from the (fine) matrix
+!  associated to the previous level, then builds the related base preconditioner.
+!  Note that this routine is only ever called on levels >= 2. 
+!
+! 
+! Arguments:
+!    p       -  type(mld_s_onelev_type), input/output.
+!               The preconditioner data structure containing the local
+!               part of the one-level preconditioner to be built.
+!    info    -  integer, output.
+!               Error code.         
+!  
+subroutine mld_saggr_bld(a,desc_a,p,info)
+
+  use psb_base_mod
+  use mld_inner_mod, mld_protect_name => mld_saggr_bld
+
+  implicit none
+
+  ! Arguments
+  type(psb_sspmat_type), intent(in), target :: a
+  type(psb_desc_type), intent(in), target   :: desc_a
+  type(mld_s_interlev_prec_type), intent(inout),target    :: p
+  integer, intent(out)                      :: info
+
+  ! Local variables
+  type(psb_desc_type)    :: desc_ac
+  type(psb_sspmat_type)  :: ac
+  character(len=20)      :: name
+  integer                :: ictxt, np, me, err_act
+
+  name='mld_saggr_bld'
+  if (psb_get_errstatus().ne.0) return 
+  call psb_erractionsave(err_act)
+  info = 0
+  ictxt = psb_cd_get_context(desc_a)
+  call psb_info(ictxt,me,np)
+
+  if (.not.allocated(p%iprcparm)) then 
+    info = 2222
+    call psb_errpush(info,name)
+    goto 9999
+  endif
+  call mld_check_def(p%iprcparm(mld_ml_type_),'Multilevel type',&
+       &   mld_mult_ml_,is_legal_ml_type)
+  call mld_check_def(p%iprcparm(mld_aggr_alg_),'Aggregation',&
+       &   mld_dec_aggr_,is_legal_ml_aggr_alg)
+  call mld_check_def(p%iprcparm(mld_aggr_kind_),'Smoother',&
+       &   mld_smooth_prol_,is_legal_ml_aggr_kind)
+  call mld_check_def(p%iprcparm(mld_coarse_mat_),'Coarse matrix',&
+       &   mld_distr_mat_,is_legal_ml_coarse_mat)
+  call mld_check_def(p%iprcparm(mld_smoother_pos_),'smooth_pos',&
+       &   mld_pre_smooth_,is_legal_ml_smooth_pos)
+  call mld_check_def(p%iprcparm(mld_aggr_omega_alg_),'Omega Alg.',&
+       &   mld_eig_est_,is_legal_ml_aggr_omega_alg)
+  call mld_check_def(p%iprcparm(mld_aggr_eig_),'Eigenvalue estimate',&
+       &   mld_max_norm_,is_legal_ml_aggr_eig)
+  call mld_check_def(p%rprcparm(mld_aggr_omega_val_),'Omega',szero,is_legal_s_omega)
+  call mld_check_def(p%rprcparm(mld_aggr_thresh_),'Aggr_Thresh',szero,is_legal_s_aggr_thrs)
+  
+
+  !
+  !  Build a mapping between the row indices of the fine-level matrix 
+  !  and the row indices of the coarse-level matrix, according to a decoupled 
+  !  aggregation algorithm. This also defines a tentative prolongator from
+  !  the coarse to the fine level.
+  ! 
+  call mld_aggrmap_bld(p%iprcparm(mld_aggr_alg_),p%rprcparm(mld_aggr_thresh_),&
+       & a,desc_a,p%nlaggr,p%mlia,info)
+  if(info /= 0) then
+    call psb_errpush(4010,name,a_err='mld_aggrmap_bld')
+    goto 9999
+  end if
+
+  !
+  ! Build the coarse-level matrix from the fine level one, starting from 
+  ! the mapping defined by mld_aggrmap_bld and applying the aggregation
+  ! algorithm specified by p%iprcparm(mld_aggr_kind_)
+  !
+  call mld_aggrmat_asb(a,desc_a,p,info)
+  if(info /= 0) then
+    call psb_errpush(4010,name,a_err='mld_aggrmat_asb')
+    goto 9999
+  end if
+  !
+  ! Fix the base_a and base_desc pointers for handling of residuals.
+  ! This is correct because this routine is only called at levels >=2.
+  !
+  p%base_a    => p%ac
+  p%base_desc => p%desc_ac
+  
+  call psb_erractionrestore(err_act)
+  return
+
+9999 continue
+  call psb_erractionrestore(err_act)
+  if (err_act.eq.psb_act_abort_) then
+    call psb_error()
+    return
+  end if
+  Return
+
+end subroutine mld_saggr_bld
diff --git a/mlprec/mld_transfer_mod.F90 b/mlprec/mld_transfer_mod.F90
new file mode 100644
index 00000000..ec6c2f48
--- /dev/null
+++ b/mlprec/mld_transfer_mod.F90
@@ -0,0 +1,453 @@
+!!$
+!!$ 
+!!$                           MLD2P4  version 1.0
+!!$  MultiLevel Domain Decomposition Parallel Preconditioners Package
+!!$             based on PSBLAS (Parallel Sparse BLAS version 2.2)
+!!$  
+!!$  (C) Copyright 2008
+!!$
+!!$                      Salvatore Filippone  University of Rome Tor Vergata       
+!!$                      Alfredo Buttari      University of Rome Tor Vergata
+!!$                      Pasqua D'Ambra       ICAR-CNR, Naples
+!!$                      Daniela di Serafino  Second University of Naples
+!!$ 
+!!$  Redistribution and use in source and binary forms, with or without
+!!$  modification, are permitted provided that the following conditions
+!!$  are met:
+!!$    1. Redistributions of source code must retain the above copyright
+!!$       notice, this list of conditions and the following disclaimer.
+!!$    2. Redistributions in binary form must reproduce the above copyright
+!!$       notice, this list of conditions, and the following disclaimer in the
+!!$       documentation and/or other materials provided with the distribution.
+!!$    3. The name of the MLD2P4 group or the names of its contributors may
+!!$       not be used to endorse or promote products derived from this
+!!$       software without specific written permission.
+!!$ 
+!!$  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+!!$  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+!!$  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+!!$  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE MLD2P4 GROUP OR ITS CONTRIBUTORS
+!!$  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+!!$  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+!!$  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+!!$  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+!!$  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+!!$  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+!!$  POSSIBILITY OF SUCH DAMAGE.
+!!$ 
+!!$
+! File: mld_transfer_mod.f90
+!
+! Package: mld_prec_type
+!          Data structure(s) for sparse matrices
+!
+!  This module defines: 
+!  - the mld_prec_type data structure containing the preconditioner;
+!  - character constants describing the preconditioner, used by the routine
+!    printing out a preconditioner description;
+!  - the interfaces to the routines for the management of the preconditioner
+!    data structure (see below).
+!
+!  It contains:
+!  - mld_dprec_sizeof, mld_dbaseprc_sizeof, mld_out_prec_descr, mld_file_prec_descr,
+!    mld_icheck_def, mld_dcheck_def, mld_dbase_precfree, mld_nullify_dbaseprec,
+!    is_legal_..._..., and their complex versions (if applicable).
+!  These routines check if the preconditioner is correctly defined,      print a
+!  description of the preconditioner, and deallocate its data structure.  
+!
+
+module mld_transfer_mod
+
+  use mld_prec_type
+
+  interface mld_transfer
+    module procedure  mld_sbaseprec_transfer, mld_sonelev_prec_transfer,&
+         & mld_sprec_transfer,&
+         & mld_dbaseprec_transfer, mld_donelev_prec_transfer,&
+         & mld_dprec_transfer,&
+         & mld_cbaseprec_transfer, mld_conelev_prec_transfer,&
+         & mld_cprec_transfer,&
+         & mld_zbaseprec_transfer, mld_zonelev_prec_transfer,&
+         & mld_zprec_transfer
+  end interface
+
+contains
+
+
+  subroutine mld_sbaseprec_transfer(a, b,info)
+    use psb_base_mod
+    implicit none
+    type(mld_sbaseprc_type), intent(inout) :: a, b
+    integer, intent(out) :: info 
+    integer :: i, isz
+    
+    call mld_precfree(b,info)
+    if (info == 0) call psb_transfer(a%iprcparm,b%iprcparm,info) 
+    if (info == 0) call psb_transfer(a%rprcparm,b%rprcparm,info) 
+    if (info == 0) call psb_transfer(a%desc_data,b%desc_data,info) 
+    if (info == 0) call psb_transfer(a%perm,b%perm,info) 
+    if (info == 0) call psb_transfer(a%invperm,b%invperm,info) 
+#ifdef HAVE_MOVE_ALLOC
+    call move_alloc(a%av,b%av)
+#else
+    if (allocated(a%av)) then 
+      isz = size(a%av)
+      allocate(b%av(isz),stat=info) 
+      do i=1,isz
+        if (info == 0) call psb_transfer(a%av(i), b%av(i), info)
+      end do
+      
+      if (info == 0) deallocate(a%av,stat=info)
+    end if
+#endif
+    if (info /= 0) then
+      write(0,*) 'Error in baseprec_:transfer',info
+    end if
+
+  end subroutine mld_sbaseprec_transfer
+
+  subroutine mld_sonelev_prec_transfer(a, b,info)
+    use psb_base_mod
+    implicit none
+    type(mld_s_interlev_prec_type), intent(inout) :: a, b
+    integer, intent(out) :: info 
+    
+    call mld_precfree(b,info)
+    if (info == 0) call mld_transfer(a%prec,b%prec,info) 
+    if (info == 0) call psb_transfer(a%iprcparm,b%iprcparm,info) 
+    if (info == 0) call psb_transfer(a%rprcparm,b%rprcparm,info) 
+    if (info == 0) call psb_transfer(a%ac,b%ac,info) 
+    if (info == 0) call psb_transfer(a%desc_ac,b%desc_ac,info) 
+    if (info == 0) call psb_transfer(a%mlia,b%mlia,info) 
+    if (info == 0) call psb_transfer(a%nlaggr,b%nlaggr,info) 
+    if (info == 0) call psb_transfer(a%map_desc,b%map_desc,info) 
+    b%base_a    => a%base_a
+    b%base_desc => a%base_desc
+    
+  end subroutine mld_sonelev_prec_transfer
+
+  subroutine mld_sprec_transfer(a, b,info)
+    use psb_base_mod
+    implicit none
+    type(mld_sprec_type), intent(inout) :: a
+    type(mld_sprec_type), intent(inout), target :: b
+    integer, intent(out) :: info 
+    integer :: i,isz
+    
+    if (allocated(b%precv)) then 
+      ! This might not be required if FINAL procedures are available.
+      call mld_precfree(b,info)
+      if (info /= 0) then 
+        !       ?????
+    !!$        return
+      endif
+    end if
+
+#ifdef HAVE_MOVE_ALLOC
+    call move_alloc(a%precv,b%precv)
+#else 
+    if (.not.allocated(a%precv)) return
+    isz = size(a%precv)
+    allocate(b%precv(isz),stat=info) 
+    if (info /= 0) then 
+      write(0,*) 'Memory allocation failure in prec_transfer'
+      return
+    end if
+    do i=1,isz
+      call mld_transfer(a%precv(i),b%precv(i),info)
+    end do
+    deallocate(a%precv,stat=info)
+#endif
+    ! Fix the pointers except on level 1.
+    do i=2, isz
+      b%precv(i)%base_a    => b%precv(i)%ac
+      b%precv(i)%base_desc => b%precv(i)%desc_ac
+      b%precv(i)%map_desc%p_desc_fw => b%precv(i-1)%base_desc
+      b%precv(i)%map_desc%p_desc_bk => b%precv(i)%base_desc
+    end do
+  end subroutine mld_sprec_transfer
+
+
+  subroutine mld_dbaseprec_transfer(a, b,info)
+    use psb_base_mod
+    implicit none
+    type(mld_dbaseprc_type), intent(inout) :: a, b
+    integer, intent(out) :: info 
+    integer :: i, isz
+    
+    call mld_precfree(b,info)
+    if (info == 0) call psb_transfer(a%iprcparm,b%iprcparm,info) 
+    if (info == 0) call psb_transfer(a%rprcparm,b%rprcparm,info) 
+    if (info == 0) call psb_transfer(a%desc_data,b%desc_data,info) 
+    if (info == 0) call psb_transfer(a%perm,b%perm,info) 
+    if (info == 0) call psb_transfer(a%invperm,b%invperm,info) 
+#ifdef HAVE_MOVE_ALLOC
+    call move_alloc(a%av,b%av)
+#else
+    if (allocated(a%av)) then 
+      isz = size(a%av)
+      allocate(b%av(isz),stat=info) 
+      do i=1,isz
+        if (info == 0) call psb_transfer(a%av(i), b%av(i), info)
+      end do
+      
+      if (info == 0) deallocate(a%av,stat=info)
+    end if
+#endif
+    if (info /= 0) then
+      write(0,*) 'Error in baseprec_:transfer',info
+    end if
+
+  end subroutine mld_dbaseprec_transfer
+
+  subroutine mld_donelev_prec_transfer(a, b,info)
+    use psb_base_mod
+    implicit none
+    type(mld_d_interlev_prec_type), intent(inout) :: a, b
+    integer, intent(out) :: info 
+    
+    call mld_precfree(b,info)
+    if (info == 0) call mld_transfer(a%prec,b%prec,info) 
+    if (info == 0) call psb_transfer(a%iprcparm,b%iprcparm,info) 
+    if (info == 0) call psb_transfer(a%rprcparm,b%rprcparm,info) 
+    if (info == 0) call psb_transfer(a%ac,b%ac,info) 
+    if (info == 0) call psb_transfer(a%desc_ac,b%desc_ac,info) 
+    if (info == 0) call psb_transfer(a%mlia,b%mlia,info) 
+    if (info == 0) call psb_transfer(a%nlaggr,b%nlaggr,info) 
+    if (info == 0) call psb_transfer(a%map_desc,b%map_desc,info) 
+    b%base_a    => a%base_a
+    b%base_desc => a%base_desc
+    
+  end subroutine mld_donelev_prec_transfer
+
+  subroutine mld_dprec_transfer(a, b,info)
+    use psb_base_mod
+    implicit none
+    type(mld_dprec_type), intent(inout) :: a
+    type(mld_dprec_type), intent(inout), target :: b
+    integer, intent(out) :: info 
+    integer :: i,isz
+    
+    if (allocated(b%precv)) then 
+      ! This might not be required if FINAL procedures are available.
+      call mld_precfree(b,info)
+      if (info /= 0) then 
+        !       ?????
+    !!$        return
+      endif
+    end if
+
+#ifdef HAVE_MOVE_ALLOC
+    call move_alloc(a%precv,b%precv)
+#else 
+    if (.not.allocated(a%precv)) return
+    isz = size(a%precv)
+    allocate(b%precv(isz),stat=info) 
+    if (info /= 0) then 
+      write(0,*) 'Memory allocation failure in prec_transfer'
+      return
+    end if
+    do i=1,isz
+      call mld_transfer(a%precv(i),b%precv(i),info)
+    end do
+    deallocate(a%precv,stat=info)
+#endif
+    ! Fix the pointers except on level 1.
+    do i=2, isz
+      b%precv(i)%base_a    => b%precv(i)%ac
+      b%precv(i)%base_desc => b%precv(i)%desc_ac
+      b%precv(i)%map_desc%p_desc_fw => b%precv(i-1)%base_desc
+      b%precv(i)%map_desc%p_desc_bk => b%precv(i)%base_desc
+    end do
+  end subroutine mld_dprec_transfer
+
+
+  subroutine mld_cbaseprec_transfer(a, b,info)
+    use psb_base_mod
+    implicit none
+    type(mld_cbaseprc_type), intent(inout) :: a, b
+    integer, intent(out) :: info 
+    integer :: i, isz
+    
+    call mld_precfree(b,info)
+    if (info == 0) call psb_transfer(a%iprcparm,b%iprcparm,info) 
+    if (info == 0) call psb_transfer(a%rprcparm,b%rprcparm,info) 
+    if (info == 0) call psb_transfer(a%desc_data,b%desc_data,info) 
+    if (info == 0) call psb_transfer(a%perm,b%perm,info) 
+    if (info == 0) call psb_transfer(a%invperm,b%invperm,info) 
+#ifdef HAVE_MOVE_ALLOC
+    call move_alloc(a%av,b%av)
+#else
+    if (allocated(a%av)) then 
+      isz = size(a%av)
+      allocate(b%av(isz),stat=info) 
+      do i=1,isz
+        if (info == 0) call psb_transfer(a%av(i), b%av(i), info)
+      end do
+      
+      if (info == 0) deallocate(a%av,stat=info)
+    end if
+#endif
+    if (info /= 0) then
+      write(0,*) 'Error in baseprec_:transfer',info
+    end if
+
+  end subroutine mld_cbaseprec_transfer
+
+  subroutine mld_conelev_prec_transfer(a, b,info)
+    use psb_base_mod
+    implicit none
+    type(mld_c_interlev_prec_type), intent(inout) :: a, b
+    integer, intent(out) :: info 
+    
+    call mld_precfree(b,info)
+    if (info == 0) call mld_transfer(a%prec,b%prec,info) 
+    if (info == 0) call psb_transfer(a%iprcparm,b%iprcparm,info) 
+    if (info == 0) call psb_transfer(a%rprcparm,b%rprcparm,info) 
+    if (info == 0) call psb_transfer(a%ac,b%ac,info) 
+    if (info == 0) call psb_transfer(a%desc_ac,b%desc_ac,info) 
+    if (info == 0) call psb_transfer(a%mlia,b%mlia,info) 
+    if (info == 0) call psb_transfer(a%nlaggr,b%nlaggr,info) 
+    if (info == 0) call psb_transfer(a%map_desc,b%map_desc,info) 
+    b%base_a    => a%base_a
+    b%base_desc => a%base_desc
+    
+  end subroutine mld_conelev_prec_transfer
+
+  subroutine mld_cprec_transfer(a, b,info)
+    use psb_base_mod
+    implicit none
+    type(mld_cprec_type), intent(inout) :: a
+    type(mld_cprec_type), intent(inout), target :: b
+    integer, intent(out) :: info 
+    integer :: i,isz
+    
+    if (allocated(b%precv)) then 
+      ! This might not be required if FINAL procedures are available.
+      call mld_precfree(b,info)
+      if (info /= 0) then 
+        !       ?????
+    !!$        return
+      endif
+    end if
+
+#ifdef HAVE_MOVE_ALLOC
+    call move_alloc(a%precv,b%precv)
+#else 
+    if (.not.allocated(a%precv)) return
+    isz = size(a%precv)
+    allocate(b%precv(isz),stat=info) 
+    if (info /= 0) then 
+      write(0,*) 'Memory allocation failure in prec_transfer'
+      return
+    end if
+    do i=1,isz
+      call mld_transfer(a%precv(i),b%precv(i),info)
+    end do
+    deallocate(a%precv,stat=info)
+#endif
+    ! Fix the pointers except on level 1.
+    do i=2, isz
+      b%precv(i)%base_a    => b%precv(i)%ac
+      b%precv(i)%base_desc => b%precv(i)%desc_ac
+      b%precv(i)%map_desc%p_desc_fw => b%precv(i-1)%base_desc
+      b%precv(i)%map_desc%p_desc_bk => b%precv(i)%base_desc
+    end do
+  end subroutine mld_cprec_transfer
+
+
+  subroutine mld_zbaseprec_transfer(a, b,info)
+    use psb_base_mod
+    implicit none
+    type(mld_zbaseprc_type), intent(inout) :: a, b
+    integer, intent(out) :: info 
+    integer :: i, isz
+    
+    call mld_precfree(b,info)
+    if (info == 0) call psb_transfer(a%iprcparm,b%iprcparm,info) 
+    if (info == 0) call psb_transfer(a%rprcparm,b%rprcparm,info) 
+    if (info == 0) call psb_transfer(a%desc_data,b%desc_data,info) 
+    if (info == 0) call psb_transfer(a%perm,b%perm,info) 
+    if (info == 0) call psb_transfer(a%invperm,b%invperm,info) 
+#ifdef HAVE_MOVE_ALLOC
+    call move_alloc(a%av,b%av)
+#else
+    if (allocated(a%av)) then 
+      isz = size(a%av)
+      allocate(b%av(isz),stat=info) 
+      do i=1,isz
+        if (info == 0) call psb_transfer(a%av(i), b%av(i), info)
+      end do
+      
+      if (info == 0) deallocate(a%av,stat=info)
+    end if
+#endif
+    if (info /= 0) then
+      write(0,*) 'Error in baseprec_:transfer',info
+    end if
+
+  end subroutine mld_zbaseprec_transfer
+
+  subroutine mld_zonelev_prec_transfer(a, b,info)
+    use psb_base_mod
+    implicit none
+    type(mld_z_interlev_prec_type), intent(inout) :: a, b
+    integer, intent(out) :: info 
+    
+    call mld_precfree(b,info)
+    if (info == 0) call mld_transfer(a%prec,b%prec,info) 
+    if (info == 0) call psb_transfer(a%iprcparm,b%iprcparm,info) 
+    if (info == 0) call psb_transfer(a%rprcparm,b%rprcparm,info) 
+    if (info == 0) call psb_transfer(a%ac,b%ac,info) 
+    if (info == 0) call psb_transfer(a%desc_ac,b%desc_ac,info) 
+    if (info == 0) call psb_transfer(a%mlia,b%mlia,info) 
+    if (info == 0) call psb_transfer(a%nlaggr,b%nlaggr,info) 
+    if (info == 0) call psb_transfer(a%map_desc,b%map_desc,info) 
+    b%base_a    => a%base_a
+    b%base_desc => a%base_desc
+    
+  end subroutine mld_zonelev_prec_transfer
+
+  subroutine mld_zprec_transfer(a, b,info)
+    use psb_base_mod
+    implicit none
+    type(mld_zprec_type), intent(inout) :: a
+    type(mld_zprec_type), intent(inout), target :: b
+    integer, intent(out) :: info 
+    integer :: i,isz
+    
+    if (allocated(b%precv)) then 
+      ! This might not be required if FINAL procedures are available.
+      call mld_precfree(b,info)
+      if (info /= 0) then 
+        !       ?????
+    !!$        return
+      endif
+    end if
+
+#ifdef HAVE_MOVE_ALLOC
+    call move_alloc(a%precv,b%precv)
+#else 
+    if (.not.allocated(a%precv)) return
+    isz = size(a%precv)
+    allocate(b%precv(isz),stat=info) 
+    if (info /= 0) then 
+      write(0,*) 'Memory allocation failure in prec_transfer'
+      return
+    end if
+    do i=1,isz
+      call mld_transfer(a%precv(i),b%precv(i),info)
+    end do
+    deallocate(a%precv,stat=info)
+#endif
+    ! Fix the pointers except on level 1.
+    do i=2, isz
+      b%precv(i)%base_a    => b%precv(i)%ac
+      b%precv(i)%base_desc => b%precv(i)%desc_ac
+      b%precv(i)%map_desc%p_desc_fw => b%precv(i-1)%base_desc
+      b%precv(i)%map_desc%p_desc_bk => b%precv(i)%base_desc
+    end do
+  end subroutine mld_zprec_transfer
+
+
+end module mld_transfer_mod
diff --git a/mlprec/mld_zaggr_bld.f90 b/mlprec/mld_zaggr_bld.f90
new file mode 100644
index 00000000..172754ea
--- /dev/null
+++ b/mlprec/mld_zaggr_bld.f90
@@ -0,0 +1,153 @@
+!!$ 
+!!$ 
+!!$                           MLD2P4  version 1.0
+!!$  MultiLevel Domain Decomposition Parallel Preconditioners Package
+!!$             based on PSBLAS (Parallel Sparse BLAS version 2.2)
+!!$  
+!!$  (C) Copyright 2008
+!!$
+!!$                      Salvatore Filippone  University of Rome Tor Vergata       
+!!$                      Alfredo Buttari      University of Rome Tor Vergata
+!!$                      Pasqua D'Ambra       ICAR-CNR, Naples
+!!$                      Daniela di Serafino  Second University of Naples
+!!$ 
+!!$  Redistribution and use in source and binary forms, with or without
+!!$  modification, are permitted provided that the following conditions
+!!$  are met:
+!!$    1. Redistributions of source code must retain the above copyright
+!!$       notice, this list of conditions and the following disclaimer.
+!!$    2. Redistributions in binary form must reproduce the above copyright
+!!$       notice, this list of conditions, and the following disclaimer in the
+!!$       documentation and/or other materials provided with the distribution.
+!!$    3. The name of the MLD2P4 group or the names of its contributors may
+!!$       not be used to endorse or promote products derived from this
+!!$       software without specific written permission.
+!!$ 
+!!$  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+!!$  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+!!$  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+!!$  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE MLD2P4 GROUP OR ITS CONTRIBUTORS
+!!$  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+!!$  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+!!$  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+!!$  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+!!$  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+!!$  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+!!$  POSSIBILITY OF SUCH DAMAGE.
+!!$ 
+!!$
+! File: mld_zaggr_bld.f90
+!
+! Subroutine: mld_zaggr_bld
+! Version:    complex
+!
+!  This routine builds the preconditioner corresponding to the current
+!  level of the multilevel preconditioner. The routine first builds the
+!  (coarse) matrix associated to the current level from the (fine) matrix
+!  associated to the previous level, then builds the related base preconditioner.
+!  Note that this routine is only ever called on levels >= 2. 
+!
+! 
+! Arguments:
+!    a       -  type(psb_dspmat_type).
+!               The sparse matrix structure containing the local part of the
+!               matrix to be preconditioned.
+!    desc_a  -  type(psb_desc_type), input.
+!               The communication descriptor of a.
+!    p       -  type(mld_z_onelev_type), input/output.
+!               The preconditioner data structure containing the local
+!               part of the one-level preconditioner to be built.
+!    info    -  integer, output.
+!               Error code.         
+!  
+subroutine mld_zaggr_bld(a,desc_a,p,info)
+
+  use psb_base_mod
+  use mld_inner_mod, mld_protect_name => mld_zaggr_bld
+
+  implicit none
+
+  ! Arguments
+  type(psb_zspmat_type), intent(in), target :: a
+  type(psb_desc_type), intent(in), target   :: desc_a
+  type(mld_z_interlev_prec_type), intent(inout),target    :: p
+  integer, intent(out)                      :: info
+
+  ! Local variables
+  type(psb_desc_type)    :: desc_ac
+  type(psb_zspmat_type)  :: ac
+  character(len=20)      :: name
+  integer                :: ictxt, np, me, err_act
+
+  name='mld_zaggr_bld'
+  if (psb_get_errstatus().ne.0) return 
+  call psb_erractionsave(err_act)
+  info = 0
+  ictxt = psb_cd_get_context(desc_a)
+  call psb_info(ictxt,me,np)
+
+  if (.not.allocated(p%iprcparm)) then 
+    info = 2222
+    call psb_errpush(info,name)
+    goto 9999
+  endif
+  call mld_check_def(p%iprcparm(mld_ml_type_),'Multilevel type',&
+       &   mld_mult_ml_,is_legal_ml_type)
+  call mld_check_def(p%iprcparm(mld_aggr_alg_),'Aggregation',&
+       &   mld_dec_aggr_,is_legal_ml_aggr_alg)
+  call mld_check_def(p%iprcparm(mld_aggr_kind_),'Smoother',&
+       &   mld_smooth_prol_,is_legal_ml_aggr_kind)
+  call mld_check_def(p%iprcparm(mld_coarse_mat_),'Coarse matrix',&
+       &   mld_distr_mat_,is_legal_ml_coarse_mat)
+  call mld_check_def(p%iprcparm(mld_smoother_pos_),'smooth_pos',&
+       &   mld_pre_smooth_,is_legal_ml_smooth_pos)
+  call mld_check_def(p%iprcparm(mld_aggr_omega_alg_),'Omega Alg.',&
+       &   mld_eig_est_,is_legal_ml_aggr_omega_alg)
+  call mld_check_def(p%iprcparm(mld_aggr_eig_),'Eigenvalue estimate',&
+       &   mld_max_norm_,is_legal_ml_aggr_eig)
+  call mld_check_def(p%rprcparm(mld_aggr_omega_val_),'Omega',dzero,is_legal_omega)
+  call mld_check_def(p%rprcparm(mld_aggr_thresh_),'Aggr_Thresh',dzero,is_legal_aggr_thrs)
+  
+
+  !
+  !  Build a mapping between the row indices of the fine-level matrix 
+  !  and the row indices of the coarse-level matrix, according to a decoupled 
+  !  aggregation algorithm. This also defines a tentative prolongator from
+  !  the coarse to the fine level.
+  ! 
+  call mld_aggrmap_bld(p%iprcparm(mld_aggr_alg_),p%rprcparm(mld_aggr_thresh_),&
+       & a,desc_a,p%nlaggr,p%mlia,info)
+  if(info /= 0) then
+    call psb_errpush(4010,name,a_err='mld_aggrmap_bld')
+    goto 9999
+  end if
+
+  !
+  ! Build the coarse-level matrix from the fine level one, starting from 
+  ! the mapping defined by mld_aggrmap_bld and applying the aggregation
+  ! algorithm specified by p%iprcparm(mld_aggr_kind_)
+  !
+  call mld_aggrmat_asb(a,desc_a,p,info)
+  if(info /= 0) then
+    call psb_errpush(4010,name,a_err='mld_aggrmat_asb')
+    goto 9999
+  end if
+  !
+  ! Fix the base_a and base_desc pointers for handling of residuals.
+  ! This is correct because this routine is only called at levels >=2.
+  !
+  p%base_a    => p%ac
+  p%base_desc => p%desc_ac
+  
+  call psb_erractionrestore(err_act)
+  return
+
+9999 continue
+  call psb_erractionrestore(err_act)
+  if (err_act.eq.psb_act_abort_) then
+    call psb_error()
+    return
+  end if
+  Return
+
+end subroutine mld_zaggr_bld