diff --git a/AABB_tree/demo/AABB_tree/CMakeLists.txt b/AABB_tree/demo/AABB_tree/CMakeLists.txt
index 84a11b6b2ea..ba6d10f7d09 100644
--- a/AABB_tree/demo/AABB_tree/CMakeLists.txt
+++ b/AABB_tree/demo/AABB_tree/CMakeLists.txt
@@ -2,6 +2,10 @@
 
 project( AABB_demo )
 
+# Find includes in corresponding build directories
+set(CMAKE_INCLUDE_CURRENT_DIR ON)
+# Instruct CMake to run moc automatically when needed.
+set(CMAKE_AUTOMOC ON)
 cmake_minimum_required(VERSION 2.6.2)
 if("${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION}.${CMAKE_PATCH_VERSION}" VERSION_GREATER 2.8.3)
   cmake_policy(VERSION 2.8.4)
@@ -11,52 +15,46 @@ endif()
 
 # Include this package's headers first
 include_directories( BEFORE ./ ./include ../../include )
-
-# Find CGAL and CGAL Qt4
-find_package(CGAL COMPONENTS Qt4)
+# Find CGAL and CGAL Qt5
+find_package(CGAL REQUIRED COMPONENTS Qt5 )
 include( ${CGAL_USE_FILE} )
 
-# Find Qt4 itself
-set( QT_USE_QTXML    TRUE )
-set( QT_USE_QTMAIN   TRUE )
-set( QT_USE_QTSCRIPT  TRUE )
-set( QT_USE_QTOPENGL  TRUE )
-find_package(Qt4)
+# Find Qt5 itself
+find_package(Qt5 COMPONENTS Xml Script OpenGL)
 
 # Find OpenGL
 find_package(OpenGL)
 
 # Find QGLViewer
-if(QT4_FOUND)
-  include(${QT_USE_FILE})
+if(Qt5_FOUND)
   find_package(QGLViewer )
-endif(QT4_FOUND)
+endif(Qt5_FOUND)
 
-if(CGAL_FOUND AND CGAL_Qt4_FOUND AND QT4_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND)
+if(CGAL_FOUND AND CGAL_Qt5_FOUND AND Qt5_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND)
 
   include_directories ( ${QGLVIEWER_INCLUDE_DIR} )
 
-  qt4_wrap_ui( UI_FILES MainWindow.ui )
+  qt5_wrap_ui( UI_FILES MainWindow.ui )
 
   include(AddFileDependencies)
 
-  qt4_generate_moc( "MainWindow.h" "${CMAKE_CURRENT_BINARY_DIR}/MainWindow_moc.cpp" )
+  qt5_generate_moc( "MainWindow.h" "${CMAKE_CURRENT_BINARY_DIR}/MainWindow_moc.cpp" )
   add_file_dependencies( MainWindow_moc.cpp "${CMAKE_CURRENT_SOURCE_DIR}/MainWindow.h" )
 
-  qt4_generate_moc( "Viewer.h" "${CMAKE_CURRENT_BINARY_DIR}/Viewer_moc.cpp" )
+  qt5_generate_moc( "Viewer.h" "${CMAKE_CURRENT_BINARY_DIR}/Viewer_moc.cpp" )
   add_file_dependencies( Viewer_moc.cpp "${CMAKE_CURRENT_SOURCE_DIR}/Viewer.h" )
 
-  qt4_generate_moc( "Scene.h" "${CMAKE_CURRENT_BINARY_DIR}/Scene_moc.cpp" )
+  qt5_generate_moc( "Scene.h" "${CMAKE_CURRENT_BINARY_DIR}/Scene_moc.cpp" )
   add_file_dependencies( Scene_moc.cpp "${CMAKE_CURRENT_SOURCE_DIR}/Scene.h" )
 
-  qt4_add_resources ( RESOURCE_FILES AABB_demo.qrc )
+  qt5_add_resources ( RESOURCE_FILES AABB_demo.qrc )
 
   add_file_dependencies( AABB_demo.cpp "${CMAKE_CURRENT_BINARY_DIR}/MainWindow_moc.cpp"
                                        "${CMAKE_CURRENT_BINARY_DIR}/Viewer_moc.cpp"
                                        "${CMAKE_CURRENT_BINARY_DIR}/Scene_moc.cpp" )
 
   add_executable  ( AABB_demo AABB_demo.cpp ${UI_FILES} ${RESOURCE_FILES} )
-
+  qt5_use_modules(AABB_demo Gui OpenGL Xml Widgets Script )
   # Link with Qt libraries
   target_link_libraries( AABB_demo ${QT_LIBRARIES} )
 
@@ -69,7 +67,7 @@ if(CGAL_FOUND AND CGAL_Qt4_FOUND AND QT4_FOUND AND OPENGL_FOUND AND QGLVIEWER_FO
   add_to_cached_list( CGAL_EXECUTABLE_TARGETS AABB_demo )
 
 
-else (CGAL_FOUND AND CGAL_CGAL_Qt4_FOUND AND QT4_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND)
+else (CGAL_FOUND AND CGAL_CGAL_Qt5_FOUND AND Qt5_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND)
 
   set(AABB_MISSING_DEPS "")
 
@@ -77,12 +75,12 @@ else (CGAL_FOUND AND CGAL_CGAL_Qt4_FOUND AND QT4_FOUND AND OPENGL_FOUND AND QGLV
     set(AABB_MISSING_DEPS "the CGAL library, ${AABB_MISSING_DEPS}")
   endif()
 
-  if(NOT CGAL_Qt4_FOUND)
-    set(AABB_MISSING_DEPS "the CGAL Qt4 library, ${AABB_MISSING_DEPS}")
+  if(NOT CGAL_Qt5_FOUND)
+    set(AABB_MISSING_DEPS "the CGAL Qt5 library, ${AABB_MISSING_DEPS}")
   endif()
 
-  if(NOT QT4_FOUND)
-    set(AABB_MISSING_DEPS "Qt4, ${AABB_MISSING_DEPS}")
+  if(NOT Qt5_FOUND)
+    set(AABB_MISSING_DEPS "Qt5, ${AABB_MISSING_DEPS}")
   endif()
 
   if(NOT OPENGL_FOUND)
@@ -95,4 +93,4 @@ else (CGAL_FOUND AND CGAL_CGAL_Qt4_FOUND AND QT4_FOUND AND OPENGL_FOUND AND QGLV
 
   message(STATUS "NOTICE: This demo requires ${AABB_MISSING_DEPS}and will not be compiled.")
 
-endif (CGAL_FOUND AND CGAL_Qt4_FOUND AND QT4_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND)
+endif (CGAL_FOUND AND CGAL_Qt5_FOUND AND Qt5_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND)
diff --git a/AABB_tree/demo/AABB_tree/Viewer.cpp b/AABB_tree/demo/AABB_tree/Viewer.cpp
index 9fadcbb847f..ea535a4ea78 100644
--- a/AABB_tree/demo/AABB_tree/Viewer.cpp
+++ b/AABB_tree/demo/AABB_tree/Viewer.cpp
@@ -2,12 +2,13 @@
 #include "Scene.h"
 #include <QMouseEvent>
 
+
+
 Viewer::Viewer(QWidget* parent)
   : QGLViewer(parent),
     m_pScene(NULL),
     m_custom_mouse(false)
 {
-  setBackgroundColor(::Qt::white);
 }
 
 void Viewer::setScene(Scene* pScene)
@@ -28,6 +29,7 @@ void Viewer::draw()
 void Viewer::initializeGL()
 {
   QGLViewer::initializeGL();
+  setBackgroundColor(::Qt::white);
 }
 
 void Viewer::mousePressEvent(QMouseEvent* e)
diff --git a/Periodic_3_triangulation_3/demo/Periodic_3_triangulation_3/CMakeLists.txt b/Periodic_3_triangulation_3/demo/Periodic_3_triangulation_3/CMakeLists.txt
index 673977d411b..0f5d07caa06 100644
--- a/Periodic_3_triangulation_3/demo/Periodic_3_triangulation_3/CMakeLists.txt
+++ b/Periodic_3_triangulation_3/demo/Periodic_3_triangulation_3/CMakeLists.txt
@@ -11,37 +11,33 @@ else()
 endif()
 
 # Find CGAL
-find_package(CGAL)
+find_package(CGAL REQUIRED COMPONENTS Qt5)
 include( ${CGAL_USE_FILE} )
 
-# Find Qt4 itself
-set ( QT_USE_QTXML    TRUE )
-set ( QT_USE_QTMAIN   TRUE )
-set ( QT_USE_QTOPENGL TRUE )
-find_package(Qt4)
+# Find Qt5 itself
+find_package(Qt5 COMPONENTS Xml OpenGL Core)
 
 # Find OpenGL
 find_package(OpenGL)
 
 # Find QGLViewer
-if(QT4_FOUND)
-  include( ${QT_USE_FILE} )
+if(Qt5_FOUND)
   find_package(QGLViewer)
-endif(QT4_FOUND)
+endif(Qt5_FOUND)
 
-if (CGAL_FOUND AND OPENGL_FOUND AND QT4_FOUND AND QGLVIEWER_FOUND AND QT_QCOLLECTIONGENERATOR_EXECUTABLE)
+if (CGAL_FOUND AND OPENGL_FOUND AND Qt5_FOUND AND QGLVIEWER_FOUND AND QT_QCOLLECTIONGENERATOR_EXECUTABLE)
 
    include_directories( ${QGLVIEWER_INCLUDE_DIR} )
 
   # UI files (Qt Designer files)
-  qt4_wrap_ui ( UI_FILES MainWindow.ui )
+  qt5_wrap_ui ( UI_FILES MainWindow.ui )
 
   # qrc files (resource files)
-  qt4_add_resources( RESOURCE_FILES ./Periodic_3_triangulation_3.qrc )
+  qt5_add_resources( RESOURCE_FILES ./Periodic_3_triangulation_3.qrc )
 
   # use the Qt MOC preprocessor on classes that derive from QObject
-  qt4_generate_moc( "Scene.h" "${CMAKE_CURRENT_BINARY_DIR}/moc_Scene.cpp" )
-  qt4_generate_moc( "MainWindow.h" "${CMAKE_CURRENT_BINARY_DIR}/moc_MainWindow.cpp" )
+  qt5_generate_moc( "Scene.h" "${CMAKE_CURRENT_BINARY_DIR}/moc_Scene.cpp" )
+  qt5_generate_moc( "MainWindow.h" "${CMAKE_CURRENT_BINARY_DIR}/moc_MainWindow.cpp" )
 
   if(DEFINED QT_QCOLLECTIONGENERATOR_EXECUTABLE)
   else()
@@ -68,21 +64,23 @@ if (CGAL_FOUND AND OPENGL_FOUND AND QT4_FOUND AND QGLVIEWER_FOUND AND QT_QCOLLEC
   		    MainWindow.ui moc_MainWindow.cpp 
 		    ${UI_FILES} ${RESOURCE_FILES} Periodic_3_triangulation_3.qhc)
 
+  qt5_use_modules(periodic_3_triangulation_3_demo Xml OpenGL)
+
   add_to_cached_list( CGAL_EXECUTABLE_TARGETS periodic_3_triangulation_3_demo)
 
   # Link the executable to CGAL and third-party libraries
   target_link_libraries(periodic_3_triangulation_3_demo ${CGAL_LIBRARIES} ${CGAL_3RD_PARTY_LIBRARIES} ${QT_LIBRARIES} ${QGLVIEWER_LIBRARIES} ${OPENGL_gl_LIBRARY} ${OPENGL_glu_LIBRARY} )
 
-else (CGAL_FOUND AND OPENGL_FOUND AND QT4_FOUND AND QGLVIEWER_FOUND AND QT_QCOLLECTIONGENERATOR_EXECUTABLE)
+else (CGAL_FOUND AND OPENGL_FOUND AND Qt5_FOUND AND QGLVIEWER_FOUND AND QT_QCOLLECTIONGENERATOR_EXECUTABLE)
 
   set(PERIODIC_TRIANGULATION_MISSING_DEPS "")
 
   if(NOT CGAL_FOUND)
-    set(PERIODIC_TRIANGULATION_MISSING_DEPS "the CGAL Qt4 library, ${PERIODIC_TRIANGULATION_MISSING_DEPS}")
+    set(PERIODIC_TRIANGULATION_MISSING_DEPS "the CGAL Qt5 library, ${PERIODIC_TRIANGULATION_MISSING_DEPS}")
   endif()
 
-  if(NOT QT4_FOUND)
-    set(PERIODIC_TRIANGULATION_MISSING_DEPS "Qt4, ${PERIODIC_TRIANGULATION_MISSING_DEPS}")
+  if(NOT Qt5_FOUND)
+    set(PERIODIC_TRIANGULATION_MISSING_DEPS "Qt5, ${PERIODIC_TRIANGULATION_MISSING_DEPS}")
   endif()
 
   if(NOT OPENGL_FOUND)
@@ -99,4 +97,4 @@ else (CGAL_FOUND AND OPENGL_FOUND AND QT4_FOUND AND QGLVIEWER_FOUND AND QT_QCOLL
 
   message(STATUS "NOTICE: This demo requires ${PERIODIC_TRIANGULATION_MISSING_DEPS}and will not be compiled.")
 
-endif (CGAL_FOUND AND OPENGL_FOUND AND QT4_FOUND AND QGLVIEWER_FOUND AND QT_QCOLLECTIONGENERATOR_EXECUTABLE)
+endif (CGAL_FOUND AND OPENGL_FOUND AND Qt5_FOUND AND QGLVIEWER_FOUND AND QT_QCOLLECTIONGENERATOR_EXECUTABLE)
diff --git a/Triangulation_3/demo/Triangulation_3/CMakeLists.txt b/Triangulation_3/demo/Triangulation_3/CMakeLists.txt
index 23bb267d739..edd72082a83 100644
--- a/Triangulation_3/demo/Triangulation_3/CMakeLists.txt
+++ b/Triangulation_3/demo/Triangulation_3/CMakeLists.txt
@@ -3,6 +3,11 @@
 
 project (Triangulation_demo_3)
 
+# Find includes in corresponding build directories
+set(CMAKE_INCLUDE_CURRENT_DIR ON)
+# Instruct CMake to run moc automatically when needed.
+set(CMAKE_AUTOMOC ON)
+
 cmake_minimum_required(VERSION 2.6.2)
 if("${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION}.${CMAKE_PATCH_VERSION}" VERSION_GREATER 2.8.3)
   cmake_policy(VERSION 2.8.4)
@@ -10,22 +15,17 @@ else()
   cmake_policy(VERSION 2.6)
 endif()
 
-find_package(CGAL  COMPONENTS Qt4)
+find_package(CGAL  COMPONENTS Qt5)
 include(${CGAL_USE_FILE})
 
 
-set( QT_USE_QTXML    TRUE )
-set( QT_USE_QTMAIN   TRUE )
-set( QT_USE_QTSCRIPT  TRUE )
-set( QT_USE_QTOPENGL  TRUE )
-find_package(Qt4)
+find_package(Qt5 COMPONENTS Xml Script OpenGL)
 
 find_package(OpenGL)
 
-if(QT4_FOUND)
-  include( ${QT_USE_FILE} )
+if(Qt5_FOUND)
   find_package(QGLViewer)
-endif(QT4_FOUND)
+endif(Qt5_FOUND)
 
 # Activate concurrency ? (turned OFF by default)
 option(ACTIVATE_CONCURRENT_TRIANGULATION_3
@@ -49,21 +49,16 @@ if( TBB_FOUND )
   include(${TBB_USE_FILE})
 endif()
 
-if ( CGAL_FOUND AND QT4_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND )
-
-  include(${QT_USE_FILE})
+if ( CGAL_FOUND AND Qt5_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND )
 
   include_directories (${QGLVIEWER_INCLUDE_DIR})
   include_directories (BEFORE ../../include ./ )
 
   # ui files, created with Qt Designer
-  qt4_wrap_ui( uis MainWindow.ui )
+  qt5_wrap_ui( uis MainWindow.ui )
 
   # qrc files (resources files, that contain icons, at least)
-  qt4_add_resources ( RESOURCE_FILES ./T3_demo.qrc )
-
-  # moc files (meta object compiler files, run moc preprocessor on the files with Widget defs)
-  qt4_automoc( MainWindow.cpp Viewer.cpp PreferenceDlg.cpp )
+  qt5_add_resources ( RESOURCE_FILES ./T3_demo.qrc )
 
 
   # cpp files
@@ -72,22 +67,23 @@ if ( CGAL_FOUND AND QT4_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND )
                     PreferenceDlg.cpp
                     Scene.cpp ${uis}  ${RESOURCE_FILES} )
 
+  qt5_use_modules(T3_demo Xml Script OpenGL)
   add_to_cached_list( CGAL_EXECUTABLE_TARGETS T3_demo )
 
   target_link_libraries( T3_demo ${CGAL_LIBRARIES} ${CGAL_3RD_PARTY_LIBRARIES})
   target_link_libraries( T3_demo ${QT_LIBRARIES} ${QGLVIEWER_LIBRARIES} ${TBB_LIBRARIES})
   target_link_libraries( T3_demo ${OPENGL_gl_LIBRARY} ${OPENGL_glu_LIBRARY} )
 
-else( CGAL_FOUND AND QT4_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND )
+else( CGAL_FOUND AND Qt5_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND )
 
   set(TRIANGULATION_3_MISSING_DEPS "")
 
   if(NOT CGAL_FOUND)
-    set(TRIANGULATION_3_MISSING_DEPS "the CGAL Qt4 library, ${TRIANGULATION_3_MISSING_DEPS}")
+    set(TRIANGULATION_3_MISSING_DEPS "the CGAL Qt5 library, ${TRIANGULATION_3_MISSING_DEPS}")
   endif()      	   
 
-  if(NOT QT4_FOUND)
-    set(TRIANGULATION_3_MISSING_DEPS "Qt4, ${TRIANGULATION_3_MISSING_DEPS}")
+  if(NOT Qt5_FOUND)
+    set(TRIANGULATION_3_MISSING_DEPS "Qt5, ${TRIANGULATION_3_MISSING_DEPS}")
   endif()      	   
 
   if(NOT OPENGL_FOUND)
@@ -101,4 +97,4 @@ else( CGAL_FOUND AND QT4_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND )
 
   message(STATUS "NOTICE: This demo requires ${TRIANGULATION_3_MISSING_DEPS}and will not be compiled.")
 
-endif( CGAL_FOUND AND QT4_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND )
+endif( CGAL_FOUND AND Qt5_FOUND AND OPENGL_FOUND AND QGLVIEWER_FOUND )