diff --git a/cmake/ACGCommon.cmake b/cmake/ACGCommon.cmake
index 200842a6..579d5b47 100644
--- a/cmake/ACGCommon.cmake
+++ b/cmake/ACGCommon.cmake
@@ -141,9 +141,22 @@ include (ACGCompiler)
 # define INCLUDE_TEMPLATES for everything we build
 add_definitions (-DINCLUDE_TEMPLATES)
 
+#unset cached qt variables which are set by all qt versions. version is the major number of the qt version (e.g. 4 or 5, not 4.8)
+macro (acg_unset_qt_shared_variables version)
+  if (ACG_INTERNAL_QT_LAST_VERSION)
+    if (NOT ${ACG_INTERNAL_QT_LAST_VERSION} EQUAL ${version})
+      unset(QT_BINARY_DIR)
+      unset(QT_PLUGINS_DIR)
+      unset(ACG_INTERNAL_QT_LAST_VERSION)
+    endif()
+  endif()
+  set (ACG_INTERNAL_QT_LAST_VERSION "${version}" CACHE INTERNAL "Qt Version, which was used on the last time")
+endmacro()
+
 # look for selected qt dependencies
 macro (acg_qt4)
   if (NOT QT4_FOUND)
+    acg_unset_qt_shared_variables(4)
     find_package (Qt4 COMPONENTS QtCore QtGui ${ARGN})
 
     set (QT_USE_QTOPENGL 1)
@@ -160,6 +173,126 @@ macro (acg_qt4)
   endif ()
 endmacro ()
 
+macro (acg_qt5)
+
+   if(POLICY CMP0020)
+     # Automatically link Qt executables to qtmain target on Windows
+     cmake_policy(SET CMP0020 NEW)
+   endif(POLICY CMP0020)
+  #if (NOT QT5_FOUND)
+
+    #set (QT_MIN_VERSION ${ARGN})
+
+  #try to find qt5 automatically
+  #for custom installation of qt5, dont use any of these variables
+  set (QT5_INSTALL_PATH "" CACHE PATH "Path to Qt5 directory which contains lib and include folder")
+  if (EXISTS "${QT5_INSTALL_PATH}")
+    set (CMAKE_PREFIX_PATH "${CMAKE_PREFIX_PATH};${QT5_INSTALL_PATH}")
+    set (QT5_INSTALL_PATH_EXISTS TRUE)
+  endif()
+  
+  
+    
+    find_package (Qt5Core QUIET)
+     
+    #find WINDOWS_SDK to avoid qt error. This must be done BEFORE Qt5Widgets is searched
+    if (Qt5Core_FOUND AND WIN32)    
+      string(REGEX REPLACE "^([0-9]+)\\.[0-9]+\\.[0-9]+.*" "\\1" QT_VERSION_MAJOR "${Qt5Core_VERSION_STRING}")
+      string(REGEX REPLACE "^[0-9]+\\.([0-9])+\\.[0-9]+.*" "\\1" QT_VERSION_MINOR "${Qt5Core_VERSION_STRING}")
+      string(REGEX REPLACE "^[0-9]+\\.[0-9]+\\.([0-9]+).*" "\\1" QT_VERSION_PATCH "${Qt5Core_VERSION_STRING}")
+    
+      if ( (QT_VERSION_MAJOR EQUAL 5) AND (QT_VERSION_MINOR LESS 3 OR ( QT_VERSION_MINOR EQUAL 3 AND QT_VERSION_PATCH EQUAL 0 )) ) # for all Qt version > 5.0.0 and < 5.3.1
+        #glu32.lib is needed by qt5 opengl version. it cannot find it by itself so we help qt
+        #this block has to be executed, before Qt5Gui is searched, otherwise we will end up with the (not so useful) QT5 error message 
+        set(WINDOWS_SDK_LIBS "COULD_NOT_FOUND" CACHE PATH "Path to the latest windows sdk libs which includes glu32.lib. Used by Qt5.")
+        if (EXISTS "${WINDOWS_SDK_LIBS}\\glu32.lib")
+          set (CMAKE_PREFIX_PATH "${CMAKE_PREFIX_PATH};${WINDOWS_SDK_LIBS}")
+        elseif(QT5_INSTALL_PATH_EXISTS) #trying to install qt5. notify about missing sdk before the qt message comes
+          message(FATAL_ERROR "Could not find glu32.lib. This is necessary for QT5 OpenGL version for windows, spleace specify glu32.lib in WINDOWS_SDK_LIB or install Qt version >= 5.3.1")
+        endif()
+      endif()    
+    endif(Qt5Core_FOUND AND WIN32)
+    
+    find_package (Qt5Widgets QUIET)    
+    find_package (Qt5Gui QUIET)
+    find_package (Qt5OpenGL QUIET)
+    
+
+    if (Qt5Core_FOUND AND Qt5Widgets_FOUND AND Qt5Gui_FOUND AND Qt5OpenGL_FOUND)
+      set (QT5_FOUND TRUE)
+    endif()
+    
+    if (QT5_FOUND)   
+      acg_unset_qt_shared_variables(5)
+    
+      #set plugin dir
+      list(GET Qt5Gui_PLUGINS 0 _plugin)
+      if (_plugin)
+        get_target_property(_plugin_full ${_plugin} LOCATION)
+        get_filename_component(_plugin_dir ${_plugin_full} PATH)
+      set (QT_PLUGINS_DIR "${_plugin_dir}/../" CACHE PATH "Path to the qt plugin directory")
+      elseif(QT5_INSTALL_PATH_EXISTS)
+        set (QT_PLUGINS_DIR "${QT5_INSTALL_PATH}/plugins/" CACHE PATH "Path to the qt plugin directory")
+      elseif()
+        set (QT_PLUGINS_DIR "QT_PLUGIN_DIR_NOT_FOUND" CACHE PATH "Path to the qt plugin directory")
+      endif(_plugin)
+      
+      #set binary dir for fixupbundle
+      if(QT5_INSTALL_PATH_EXISTS)
+        set(_QT_BINARY_DIR "${QT5_INSTALL_PATH}/bin")
+      else()
+        get_target_property(_QT_BINARY_DIR ${Qt5Widgets_UIC_EXECUTABLE} LOCATION)
+        get_filename_component(_QT_BINARY_DIR ${_QT_BINARY_DIR} PATH)
+      endif(QT5_INSTALL_PATH_EXISTS)
+      
+      set (QT_BINARY_DIR "${_QT_BINARY_DIR}" CACHE PATH "Qt5 binary Directory")
+      mark_as_advanced(QT_BINARY_DIR)
+      
+      set (CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
+  
+      include_directories(${Qt5Core_INCLUDE_DIRS})
+      include_directories(${Qt5Widgets_INCLUDE_DIRS})
+      include_directories(${Qt5Gui_INCLUDE_DIRS})
+      include_directories(${Qt5OpenGL_INCLUDE_DIRS})
+      add_definitions(${Qt5Core_DEFINITIONS})
+      add_definitions(${Qt5Widgets_DEFINITIONS})
+      add_definitions(${Qt5Gui_DEFINITIONS})
+      add_definitions(${Qt5OpenGL_DEFINITIONS})
+      
+      if ( NOT MSVC )
+        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIC")
+      endif()
+
+      set (QT_LIBRARIES ${Qt5Core_LIBRARIES} ${Qt5Widgets_LIBRARIES}
+        ${Qt5Gui_LIBRARIES} ${Qt5OpenGL_LIBRARIES})
+       
+      if (MSVC)
+        set (QT_LIBRARIES ${QT_LIBRARIES} ${Qt5Core_QTMAIN_LIBRARIES})
+      endif()
+
+    #add_definitions(-DQT_NO_OPENGL)
+
+    #adding QT_NO_DEBUG to all release modes. 
+    #  Note: for multi generators like msvc you cannot set this definition depending of
+    #  the current build type, because it may change in the future inside the ide and not via cmake
+    if (MSVC_IDE)
+      set(CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE} /DQT_NO_DEBUG")
+      set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE} /DQT_NO_DEBUG")
+    
+    set(CMAKE_C_FLAGS_MINSIZEREL "${CMAKE_C_FLAGS_RELEASE} /DQT_NO_DEBUG")
+      set(CMAKE_CXX_FLAGS_MINSITEREL "${CMAKE_C_FLAGS_RELEASE} /DQT_NO_DEBUG")
+    
+    set(CMAKE_C_FLAGS_RELWITHDEBINFO "${CMAKE_C_FLAGS_RELEASE} /DQT_NO_DEBUG")
+      set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "${CMAKE_C_FLAGS_RELEASE} /DQT_NO_DEBUG")
+    else(MSVC_IDE)
+      if(NOT CMAKE_BUILD_TYPE STREQUAL "Debug")
+        add_definitions(-DQT_NO_DEBUG)
+      endif()
+    endif(MSVC_IDE)
+
+    endif ()
+endmacro ()
+
 # unsets the given variable
 macro (acg_unset var)
     set (${var} "" CACHE INTERNAL "")
@@ -282,6 +415,51 @@ macro (acg_qt4_automoc moc_SRCS)
   endforeach ()
 endmacro ()
 
+# generate moc targets for sources in list
+macro (acg_qt5_automoc moc_SRCS)
+  qt5_get_moc_flags (_moc_INCS)
+  
+  list(REMOVE_DUPLICATES _moc_INCS)
+
+  set (_matching_FILES )
+  foreach (_current_FILE ${ARGN})
+
+     get_filename_component (_abs_FILE ${_current_FILE} ABSOLUTE)
+     # if "SKIP_AUTOMOC" is set to true, we will not handle this file here.
+     # here. this is required to make bouic work correctly:
+     # we need to add generated .cpp files to the sources (to compile them),
+     # but we cannot let automoc handle them, as the .cpp files don't exist yet when
+     # cmake is run for the very first time on them -> however the .cpp files might
+     # exist at a later run. at that time we need to skip them, so that we don't add two
+     # different rules for the same moc file
+     get_source_file_property (_skip ${_abs_FILE} SKIP_AUTOMOC)
+
+     if ( NOT _skip AND EXISTS ${_abs_FILE} )
+
+        file (READ ${_abs_FILE} _contents)
+
+        get_filename_component (_abs_PATH ${_abs_FILE} PATH)
+
+        string (REGEX MATCHALL "Q_OBJECT" _match "${_contents}")
+        if (_match)
+            get_filename_component (_basename ${_current_FILE} NAME_WE)
+            set (_header ${_abs_FILE})
+            set (_moc    ${CMAKE_CURRENT_BINARY_DIR}/moc_${_basename}.cpp)
+
+            add_custom_command (OUTPUT ${_moc}
+                COMMAND ${QT_MOC_EXECUTABLE}
+                ARGS ${_moc_INCS} ${_header} -o ${_moc}
+                DEPENDS ${_header}
+            )
+
+            add_file_dependencies (${_abs_FILE} ${_moc})
+            set (${moc_SRCS} ${${moc_SRCS}} ${_moc})
+
+        endif ()
+     endif ()
+  endforeach ()
+endmacro ()
+
 # generate uic targets for sources in list
 macro (acg_qt4_autouic uic_SRCS)
 
@@ -314,6 +492,37 @@ macro (acg_qt4_autouic uic_SRCS)
   endforeach ()
 endmacro ()
 
+# generate uic targets for sources in list
+macro (acg_qt5_autouic uic_SRCS)
+
+  set (_matching_FILES )
+  foreach (_current_FILE ${ARGN})
+
+     get_filename_component (_abs_FILE ${_current_FILE} ABSOLUTE)
+
+     if ( EXISTS ${_abs_FILE} )
+
+        file (READ ${_abs_FILE} _contents)
+
+        get_filename_component (_abs_PATH ${_abs_FILE} PATH)
+
+        get_filename_component (_basename ${_current_FILE} NAME_WE)
+        string (REGEX REPLACE "Ui$" "" _cbasename ${_basename})
+        set (_outfile ${CMAKE_CURRENT_BINARY_DIR}/ui_${_basename}.hh)
+        set (_header ${_basename}.hh)
+        set (_source ${_abs_PATH}/${_cbasename}.cc)
+
+        add_custom_command (OUTPUT ${_outfile}
+            COMMAND ${Qt5Widgets_UIC_EXECUTABLE}
+            ARGS -o ${_outfile} ${_abs_FILE}
+            MAIN_DEPENDENCY ${_abs_FILE} VERBATIM)
+
+        add_file_dependencies (${_source} ${_outfile})
+        set (${uic_SRCS} ${${uic_SRCS}} ${_outfile})
+
+     endif ()
+  endforeach ()
+endmacro ()
 
 # generate qrc targets for sources in list
 macro (acg_qt4_autoqrc qrc_SRCS)
diff --git a/src/OpenMesh/Apps/CMakeLists.txt b/src/OpenMesh/Apps/CMakeLists.txt
index 0063b740..15c7cd49 100644
--- a/src/OpenMesh/Apps/CMakeLists.txt
+++ b/src/OpenMesh/Apps/CMakeLists.txt
@@ -41,8 +41,14 @@ if ( BUILD_APPS )
     find_package (OpenGL)
     find_package (GLUT)
 
+    # try to use QT5 if possible otherwise stick to QT4
+    set (FORCE_QT4 OFF CACHE BOOL "Use Qt4 even if Qt5 was found")
+
     # For the apps, we need qt and opengl to build them
-    if (NOT QT4_FOUND)
+    if (NOT QT5_FOUND AND NOT FORCE_QT4)
+      acg_qt5 ()
+    endif()
+    if (NOT QT5_FOUND AND NOT QT4_FOUND)
       find_package (Qt4 COMPONENTS QtCore QtGui )
 
       set (QT_USE_QTOPENGL 1)
@@ -55,7 +61,8 @@ if ( BUILD_APPS )
     endif()
 
     # check for OpenGL and GLUT as our required dependencies
-    if (QT4_FOUND AND OPENGL_FOUND AND GLUT_FOUND AND NOT "${CMAKE_GENERATOR}" MATCHES "MinGW Makefiles" )
+    if ((QT5_FOUND OR QT4_FOUND) AND OPENGL_FOUND AND GLUT_FOUND AND NOT "${CMAKE_GENERATOR}" MATCHES "MinGW Makefiles" )
+
       add_subdirectory (Decimating/DecimaterGui)
       add_subdirectory (QtViewer)
       add_subdirectory (Subdivider/SubdividerGui)
diff --git a/src/OpenMesh/Apps/Decimating/DecimaterGui/CMakeLists.txt b/src/OpenMesh/Apps/Decimating/DecimaterGui/CMakeLists.txt
index 0749f13e..89d0596a 100644
--- a/src/OpenMesh/Apps/Decimating/DecimaterGui/CMakeLists.txt
+++ b/src/OpenMesh/Apps/Decimating/DecimaterGui/CMakeLists.txt
@@ -30,7 +30,11 @@ set (sources
 acg_drop_templates (sources)
 
 # genereate uic and moc targets
-acg_qt4_automoc (moc_targets ${headers})
+if(QT5_FOUND)
+  acg_qt5_automoc (moc_targets ${headers})
+else()
+  acg_qt4_automoc (moc_targets ${headers})
+endif()
 
 if (WIN32)
   acg_add_executable (${targetName} WIN32 ${sources} ${headers} ${moc_targets})
diff --git a/src/OpenMesh/Apps/ProgViewer/CMakeLists.txt b/src/OpenMesh/Apps/ProgViewer/CMakeLists.txt
index bdbecc90..092d46cc 100644
--- a/src/OpenMesh/Apps/ProgViewer/CMakeLists.txt
+++ b/src/OpenMesh/Apps/ProgViewer/CMakeLists.txt
@@ -40,7 +40,11 @@ list (APPEND headers "../QtViewer/MeshViewerWidgetT.hh")
 acg_drop_templates (sources)
 
 # genereate uic and moc targets
-acg_qt4_automoc (moc_targets ${headers})
+if(QT5_FOUND)
+  acg_qt5_automoc (moc_targets ${headers})
+else()
+  acg_qt4_automoc (moc_targets ${headers})
+endif()
 
 if (WIN32)
   acg_add_executable (${targetName} WIN32 ${sources} ${headers} ${moc_targets})
diff --git a/src/OpenMesh/Apps/QtViewer/CMakeLists.txt b/src/OpenMesh/Apps/QtViewer/CMakeLists.txt
index 5599334f..c3ac4846 100644
--- a/src/OpenMesh/Apps/QtViewer/CMakeLists.txt
+++ b/src/OpenMesh/Apps/QtViewer/CMakeLists.txt
@@ -23,8 +23,13 @@ acg_append_files (ui "*.ui" ${directories})
 acg_drop_templates (sources)
 
 # genereate uic and moc targets
-acg_qt4_autouic (uic_targets ${ui})
-acg_qt4_automoc (moc_targets ${headers})
+if(QT5_FOUND)
+  acg_qt5_autouic (uic_targets ${ui})
+  acg_qt5_automoc (moc_targets ${headers})
+else()
+  acg_qt4_autouic (uic_targets ${ui})
+  acg_qt4_automoc (moc_targets ${headers})
+endif()
 
 
 if (WIN32)
diff --git a/src/OpenMesh/Apps/QtViewer/QGLViewerWidget.hh b/src/OpenMesh/Apps/QtViewer/QGLViewerWidget.hh
index 35d50bfb..3d4a8223 100644
--- a/src/OpenMesh/Apps/QtViewer/QGLViewerWidget.hh
+++ b/src/OpenMesh/Apps/QtViewer/QGLViewerWidget.hh
@@ -48,7 +48,7 @@
 
 
 #include <OpenMesh/Core/Geometry/VectorT.hh>
-#include <QtOpenGL/qgl.h>
+#include <QGLWidget>
 #include <string>
 #include <vector>
 #include <map>
diff --git a/src/OpenMesh/Apps/Subdivider/SubdivideWidget.cc b/src/OpenMesh/Apps/Subdivider/SubdivideWidget.cc
index f9defdae..ead70ff9 100644
--- a/src/OpenMesh/Apps/Subdivider/SubdivideWidget.cc
+++ b/src/OpenMesh/Apps/Subdivider/SubdivideWidget.cc
@@ -139,7 +139,7 @@ SubdivideWidget(QWidget* _parent, const char* _name)
   
   QButtonGroup* buttonGroup = new QButtonGroup();
 
-  buttonGroup->setExclusive( TRUE );
+  buttonGroup->setExclusive( true );
 
   // insert 2 radiobuttons
   QRadioButton* radio1 = new QRadioButton( "Comp. Loop" );
@@ -149,7 +149,7 @@ SubdivideWidget(QWidget* _parent, const char* _name)
   QRadioButton* radio5 = new QRadioButton( "Interpolating Sqrt3" );
   QRadioButton* radio6 = new QRadioButton( "Modified Butterfly" );
   // QRadioButton* radio7 = new QRadioButton( "Catmull Clark" ); // Disabled, as it needs a quad mesh!
-  radio3->setChecked( TRUE );
+  radio3->setChecked( true );
   sel_topo_type = SOP_UniformLoop;
 
   buttonGroup->addButton(radio1, SOP_UniformCompositeLoop);
diff --git a/src/OpenMesh/Apps/Subdivider/SubdividerGui/CMakeLists.txt b/src/OpenMesh/Apps/Subdivider/SubdividerGui/CMakeLists.txt
index 9d1c436a..abc8f9f1 100644
--- a/src/OpenMesh/Apps/Subdivider/SubdividerGui/CMakeLists.txt
+++ b/src/OpenMesh/Apps/Subdivider/SubdividerGui/CMakeLists.txt
@@ -29,7 +29,11 @@ set (sources
 acg_drop_templates (sources)
 
 # genereate uic and moc targets
-acg_qt4_automoc (moc_targets ${headers})
+if(QT5_FOUND)
+  acg_qt5_automoc (moc_targets ${headers})
+else()
+  acg_qt4_automoc (moc_targets ${headers})
+endif()
 
 if (WIN32)
   acg_add_executable (${targetName} WIN32 ${sources} ${headers} ${moc_targets})
diff --git a/src/OpenMesh/Apps/VDProgMesh/Synthesizer/CMakeLists.txt b/src/OpenMesh/Apps/VDProgMesh/Synthesizer/CMakeLists.txt
index 858ffa2c..ac1216ed 100644
--- a/src/OpenMesh/Apps/VDProgMesh/Synthesizer/CMakeLists.txt
+++ b/src/OpenMesh/Apps/VDProgMesh/Synthesizer/CMakeLists.txt
@@ -23,7 +23,11 @@ list (APPEND headers "../../QtViewer/MeshViewerWidgetT.hh")
 acg_drop_templates (sources)
 
 # genereate uic and moc targets
-acg_qt4_automoc (moc_targets ${headers})
+if(QT5_FOUND)
+  acg_qt5_automoc (moc_targets ${headers})
+else()
+  acg_qt4_automoc (moc_targets ${headers})
+endif()
 
 if (WIN32)
   acg_add_executable (${targetName} WIN32 ${sources} ${headers} ${moc_targets})