diff --git a/dbsim/db_storage_engine.hpp b/dbsim/db_storage_engine.hpp
index 0721a2a..de5080c 100644
--- a/dbsim/db_storage_engine.hpp
+++ b/dbsim/db_storage_engine.hpp
@@ -23,7 +23,8 @@
 #include "db_params.hpp"
 
 #include "wsrep/mutex.hpp"
-#include "wsrep/client_state.hpp"
+#include "wsrep/view.hpp"
+#include "wsrep/transaction.hpp"
 
 #include <atomic>
 #include <unordered_set>
diff --git a/include/wsrep/client_state.hpp b/include/wsrep/client_state.hpp
index 138bf5f..e740370 100644
--- a/include/wsrep/client_state.hpp
+++ b/include/wsrep/client_state.hpp
@@ -31,12 +31,9 @@
 #ifndef WSREP_CLIENT_STATE_HPP
 #define WSREP_CLIENT_STATE_HPP
 
-#include "server_state.hpp"
-#include "server_service.hpp"
 #include "provider.hpp"
 #include "transaction.hpp"
 #include "client_id.hpp"
-#include "client_service.hpp"
 #include "mutex.hpp"
 #include "lock.hpp"
 #include "buffer.hpp"
@@ -46,8 +43,10 @@
 
 namespace wsrep
 {
+    class client_service;
     class server_state;
     class provider;
+    class condition_variable;
 
     enum client_error
     {
diff --git a/include/wsrep/high_priority_service.hpp b/include/wsrep/high_priority_service.hpp
index f1d011e..79b9f09 100644
--- a/include/wsrep/high_priority_service.hpp
+++ b/include/wsrep/high_priority_service.hpp
@@ -24,11 +24,11 @@
 #ifndef WSREP_HIGH_PRIORITY_SERVICE_HPP
 #define WSREP_HIGH_PRIORITY_SERVICE_HPP
 
-#include "xid.hpp"
 #include "server_state.hpp"
 
 namespace wsrep
 {
+    class xid;
     class ws_handle;
     class ws_meta;
     class const_buffer;
diff --git a/include/wsrep/transaction.hpp b/include/wsrep/transaction.hpp
index 76835fd..fb69b35 100644
--- a/include/wsrep/transaction.hpp
+++ b/include/wsrep/transaction.hpp
@@ -22,13 +22,11 @@
 #define WSREP_TRANSACTION_HPP
 
 #include "provider.hpp"
-#include "server_state.hpp"
 #include "transaction_id.hpp"
 #include "streaming_context.hpp"
 #include "lock.hpp"
 #include "sr_key_set.hpp"
 #include "buffer.hpp"
-#include "client_service.hpp"
 #include "xid.hpp"
 
 #include <cassert>
@@ -40,6 +38,7 @@ namespace wsrep
     class client_state;
     class key;
     class const_buffer;
+    class server_service;
 
     class transaction
     {
diff --git a/src/client_state.cpp b/src/client_state.cpp
index 9d0a816..c547373 100644
--- a/src/client_state.cpp
+++ b/src/client_state.cpp
@@ -20,6 +20,9 @@
 #include "wsrep/client_state.hpp"
 #include "wsrep/compiler.hpp"
 #include "wsrep/logger.hpp"
+#include "wsrep/server_state.hpp"
+#include "wsrep/server_service.hpp"
+#include "wsrep/client_service.hpp"
 
 #include <unistd.h> // usleep()
 #include <sstream>
diff --git a/src/server_state.cpp b/src/server_state.cpp
index 88ec12b..d75ffd8 100644
--- a/src/server_state.cpp
+++ b/src/server_state.cpp
@@ -20,6 +20,7 @@
 #include "wsrep/server_state.hpp"
 #include "wsrep/client_state.hpp"
 #include "wsrep/server_service.hpp"
+#include "wsrep/client_service.hpp"
 #include "wsrep/high_priority_service.hpp"
 #include "wsrep/transaction.hpp"
 #include "wsrep/view.hpp"
diff --git a/src/transaction.cpp b/src/transaction.cpp
index 2480374..879cc23 100644
--- a/src/transaction.cpp
+++ b/src/transaction.cpp
@@ -25,6 +25,8 @@
 #include "wsrep/key.hpp"
 #include "wsrep/logger.hpp"
 #include "wsrep/compiler.hpp"
+#include "wsrep/server_service.hpp"
+#include "wsrep/client_service.hpp"
 
 #include <sstream>
 #include <memory>
diff --git a/test/mock_client_state.hpp b/test/mock_client_state.hpp
index 56434f7..041c4fd 100644
--- a/test/mock_client_state.hpp
+++ b/test/mock_client_state.hpp
@@ -23,6 +23,8 @@
 #include "wsrep/client_state.hpp"
 #include "wsrep/mutex.hpp"
 #include "wsrep/compiler.hpp"
+#include "wsrep/client_service.hpp"
+#include "wsrep/condition_variable.hpp"
 
 #include "test_utils.hpp"