diff --git a/src/muz/spacer/obj_equiv_class.h b/src/muz/spacer/obj_equiv_class.h
index b3184655c..7f58efa7d 100644
--- a/src/muz/spacer/obj_equiv_class.h
+++ b/src/muz/spacer/obj_equiv_class.h
@@ -25,8 +25,8 @@ Revision History:
 #ifndef OBJ_EQUIV_CLASS_H_
 #define OBJ_EQUIV_CLASS_H_
 
-#include "union_find.h"
-#include "ast_util.h"
+#include "util/union_find.h"
+#include "ast/ast_util.h"
 
 namespace spacer {
 //All functions naturally add their parameters to the union_find class
diff --git a/src/muz/spacer/spacer_antiunify.cpp b/src/muz/spacer/spacer_antiunify.cpp
index 56fbbb8f0..6c382a723 100644
--- a/src/muz/spacer/spacer_antiunify.cpp
+++ b/src/muz/spacer/spacer_antiunify.cpp
@@ -18,13 +18,13 @@ Revision History:
 
 --*/
 
-#include"spacer_antiunify.h"
-#include"ast.h"
-#include"rewriter.h"
-#include"rewriter_def.h"
-#include"arith_decl_plugin.h"
-#include"ast_util.h"
-#include"expr_abstract.h"
+#include"muz/spacer/spacer_antiunify.h"
+#include"ast/ast.h"
+#include"ast/rewriter/rewriter.h"
+#include"ast/rewriter/rewriter_def.h"
+#include"ast/arith_decl_plugin.h"
+#include"ast/ast_util.h"
+#include"ast/expr_abstract.h"
 
 namespace spacer {
 
diff --git a/src/muz/spacer/spacer_antiunify.h b/src/muz/spacer/spacer_antiunify.h
index 690bc4678..2b86f67ec 100644
--- a/src/muz/spacer/spacer_antiunify.h
+++ b/src/muz/spacer/spacer_antiunify.h
@@ -21,7 +21,7 @@ Revision History:
 #ifndef _SPACER_ANTIUNIFY_H_
 #define _SPACER_ANTIUNIFY_H_
 
-#include "ast.h"
+#include "ast/ast.h"
 
 namespace spacer {
 class anti_unifier
diff --git a/src/muz/spacer/spacer_context.cpp b/src/muz/spacer/spacer_context.cpp
index 40709de7f..a8ee01cff 100644
--- a/src/muz/spacer/spacer_context.cpp
+++ b/src/muz/spacer/spacer_context.cpp
@@ -24,34 +24,33 @@ Notes:
 #include <sstream>
 #include <iomanip>
 
-#include "dl_util.h"
-#include "rewriter.h"
-#include "rewriter_def.h"
-#include "var_subst.h"
-#include "util.h"
-#include "spacer_prop_solver.h"
-#include "spacer_context.h"
-#include "spacer_generalizers.h"
-#include "for_each_expr.h"
-#include "dl_rule_set.h"
-#include "unit_subsumption_tactic.h"
-#include "model_smt2_pp.h"
-#include "dl_mk_rule_inliner.h"
-#include "ast_smt2_pp.h"
-#include "ast_ll_pp.h"
-#include "ast_util.h"
-#include "proof_checker.h"
-#include "smt_value_sort.h"
-#include "proof_utils.h"
-#include "scoped_proof.h"
-#include "spacer_qe_project.h"
-#include "blast_term_ite_tactic.h"
+#include "muz/base/dl_util.h"
+#include "ast/rewriter/rewriter.h"
+#include "ast/rewriter/rewriter_def.h"
+#include "ast/rewriter/var_subst.h"
+#include "util/util.h"
+#include "muz/spacer/spacer_prop_solver.h"
+#include "muz/spacer/spacer_context.h"
+#include "muz/spacer/spacer_generalizers.h"
+#include "ast/for_each_expr.h"
+#include "muz/base/dl_rule_set.h"
+#include "smt/tactic/unit_subsumption_tactic.h"
+#include "model/model_smt2_pp.h"
+#include "muz/transforms/dl_mk_rule_inliner.h"
+#include "ast/ast_smt2_pp.h"
+#include "ast/ast_ll_pp.h"
+#include "ast/ast_util.h"
+#include "ast/proof_checker/proof_checker.h"
+#include "smt/smt_value_sort.h"
+#include "ast/scoped_proof.h"
+#include "muz/spacer/spacer_qe_project.h"
+#include "tactic/core/blast_term_ite_tactic.h"
 
-#include "timeit.h"
-#include "luby.h"
-#include "expr_safe_replace.h"
-#include "expr_abstract.h"
-#include "obj_equiv_class.h"
+#include "util/timeit.h"
+#include "util/luby.h"
+#include "ast/rewriter/expr_safe_replace.h"
+#include "ast/expr_abstract.h"
+#include "muz/spacer/obj_equiv_class.h"
 
 namespace spacer {
 
diff --git a/src/muz/spacer/spacer_dl_interface.cpp b/src/muz/spacer/spacer_dl_interface.cpp
index 264809f72..78776e074 100644
--- a/src/muz/spacer/spacer_dl_interface.cpp
+++ b/src/muz/spacer/spacer_dl_interface.cpp
@@ -17,23 +17,23 @@ Revision History:
 
 --*/
 
-#include "dl_context.h"
-#include "dl_mk_coi_filter.h"
-#include "dl_mk_interp_tail_simplifier.h"
-#include "dl_mk_subsumption_checker.h"
-#include "dl_mk_rule_inliner.h"
-#include "dl_rule.h"
-#include "dl_rule_transformer.h"
-#include "smt2parser.h"
-#include "spacer_context.h"
-#include "spacer_dl_interface.h"
-#include "dl_rule_set.h"
-#include "dl_mk_slice.h"
-#include "dl_mk_unfold.h"
-#include "dl_mk_coalesce.h"
-#include "model_smt2_pp.h"
-#include "scoped_proof.h"
-#include "dl_transforms.h"
+#include "muz/base/dl_context.h"
+#include "muz/transforms/dl_mk_coi_filter.h"
+#include "muz/transforms/dl_mk_interp_tail_simplifier.h"
+#include "muz/transforms/dl_mk_subsumption_checker.h"
+#include "muz/transforms/dl_mk_rule_inliner.h"
+#include "muz/base/dl_rule.h"
+#include "muz/base/dl_rule_transformer.h"
+#include "parsers/smt2/smt2parser.h"
+#include "muz/spacer/spacer_context.h"
+#include "muz/spacer/spacer_dl_interface.h"
+#include "muz/base/dl_rule_set.h"
+#include "muz/transforms/dl_mk_slice.h"
+#include "muz/transforms/dl_mk_unfold.h"
+#include "muz/transforms/dl_mk_coalesce.h"
+#include "model/model_smt2_pp.h"
+#include "ast/scoped_proof.h"
+#include "muz/transforms/dl_transforms.h"
 
 using namespace spacer;
 
diff --git a/src/muz/spacer/spacer_dl_interface.h b/src/muz/spacer/spacer_dl_interface.h
index 809f6fc83..1581762d5 100644
--- a/src/muz/spacer/spacer_dl_interface.h
+++ b/src/muz/spacer/spacer_dl_interface.h
@@ -19,11 +19,11 @@ Revision History:
 #ifndef _SPACER_DL_INTERFACE_H_
 #define _SPACER_DL_INTERFACE_H_
 
-#include "lbool.h"
-#include "dl_rule.h"
-#include "dl_rule_set.h"
-#include "dl_engine_base.h"
-#include "statistics.h"
+#include "util/lbool.h"
+#include "muz/base/dl_rule.h"
+#include "muz/base/dl_rule_set.h"
+#include "muz/base/dl_engine_base.h"
+#include "util/statistics.h"
 
 namespace datalog {
 class context;
diff --git a/src/muz/spacer/spacer_farkas_learner.cpp b/src/muz/spacer/spacer_farkas_learner.cpp
index edee8ba6f..29d238cc9 100644
--- a/src/muz/spacer/spacer_farkas_learner.cpp
+++ b/src/muz/spacer/spacer_farkas_learner.cpp
@@ -19,21 +19,21 @@ Revision History:
 --*/
 
 //TODO: reorder, delete unnecessary includes
-#include "ast_smt2_pp.h"
-#include "array_decl_plugin.h"
-#include "bool_rewriter.h"
-#include "dl_decl_plugin.h"
-#include "for_each_expr.h"
-#include "dl_util.h"
-#include "rewriter.h"
-#include "rewriter_def.h"
-#include "spacer_util.h"
-#include "spacer_farkas_learner.h"
-#include "th_rewriter.h"
-#include "ast_ll_pp.h"
-#include "proof_utils.h"
-#include "reg_decl_plugins.h"
-#include "smt_farkas_util.h"
+#include "ast/ast_smt2_pp.h"
+#include "ast/array_decl_plugin.h"
+#include "ast/rewriter/bool_rewriter.h"
+#include "ast/dl_decl_plugin.h"
+#include "ast/for_each_expr.h"
+#include "muz/base/dl_util.h"
+#include "ast/rewriter/rewriter.h"
+#include "ast/rewriter/rewriter_def.h"
+#include "muz/spacer/spacer_util.h"
+#include "muz/spacer/spacer_farkas_learner.h"
+#include "ast/rewriter/th_rewriter.h"
+#include "ast/ast_ll_pp.h"
+#include "muz/base/proof_utils.h"
+#include "ast/reg_decl_plugins.h"
+#include "smt/smt_farkas_util.h"
 
 namespace spacer {
 
@@ -437,4 +437,3 @@ bool farkas_learner::is_farkas_lemma(ast_manager& m, expr* e)
         d->get_num_parameters() >= m.get_num_parents(to_app(e)) + 2;
 }
 }
-
diff --git a/src/muz/spacer/spacer_farkas_learner.h b/src/muz/spacer/spacer_farkas_learner.h
index 7a0abf6f5..724b18b73 100644
--- a/src/muz/spacer/spacer_farkas_learner.h
+++ b/src/muz/spacer/spacer_farkas_learner.h
@@ -20,7 +20,7 @@ Revision History:
 #ifndef _SPACER_FARKAS_LEARNER_H_
 #define _SPACER_FARKAS_LEARNER_H_
 
-#include "ast.h"
+#include "ast/ast.h"
 
 namespace spacer {
 
diff --git a/src/muz/spacer/spacer_generalizers.cpp b/src/muz/spacer/spacer_generalizers.cpp
index f36983077..9f8757024 100644
--- a/src/muz/spacer/spacer_generalizers.cpp
+++ b/src/muz/spacer/spacer_generalizers.cpp
@@ -19,12 +19,12 @@ Revision History:
 --*/
 
 
-#include "spacer_context.h"
-#include "spacer_generalizers.h"
-#include "expr_abstract.h"
-#include "var_subst.h"
-#include "for_each_expr.h"
-#include "obj_equiv_class.h"
+#include "muz/spacer/spacer_context.h"
+#include "muz/spacer/spacer_generalizers.h"
+#include "ast/expr_abstract.h"
+#include "ast/rewriter/var_subst.h"
+#include "ast/for_each_expr.h"
+#include "muz/spacer/obj_equiv_class.h"
 
 
 namespace spacer {
diff --git a/src/muz/spacer/spacer_generalizers.h b/src/muz/spacer/spacer_generalizers.h
index 8634f0828..aa542ec04 100644
--- a/src/muz/spacer/spacer_generalizers.h
+++ b/src/muz/spacer/spacer_generalizers.h
@@ -20,8 +20,8 @@ Revision History:
 #ifndef _SPACER_GENERALIZERS_H_
 #define _SPACER_GENERALIZERS_H_
 
-#include "spacer_context.h"
-#include "arith_decl_plugin.h"
+#include "muz/spacer/spacer_context.h"
+#include "ast/arith_decl_plugin.h"
 
 namespace spacer {