diff --git a/AABB_tree/demo/AABB_tree/CMakeLists.txt b/AABB_tree/demo/AABB_tree/CMakeLists.txt
index eb4f6a96fca..cec72a6421c 100644
--- a/AABB_tree/demo/AABB_tree/CMakeLists.txt
+++ b/AABB_tree/demo/AABB_tree/CMakeLists.txt
@@ -14,7 +14,7 @@ endif()
 # Include this package's headers first
 include_directories( BEFORE ./ ./include ../../include )
 # Find CGAL and CGAL Qt5
-find_package(CGAL REQUIRED COMPONENTS Qt5 )
+find_package(CGAL COMPONENTS Qt5 )
 include( ${CGAL_USE_FILE} )
 
 # Find Qt5 itself
diff --git a/Alpha_shapes_3/demo/Alpha_shapes_3/CMakeLists.txt b/Alpha_shapes_3/demo/Alpha_shapes_3/CMakeLists.txt
index 668afba7b39..6161c34ca8f 100644
--- a/Alpha_shapes_3/demo/Alpha_shapes_3/CMakeLists.txt
+++ b/Alpha_shapes_3/demo/Alpha_shapes_3/CMakeLists.txt
@@ -11,7 +11,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 include(${CGAL_USE_FILE})
 
 find_package(Qt5 COMPONENTS Xml Script OpenGL)
diff --git a/Circular_kernel_3/demo/Circular_kernel_3/CMakeLists.txt b/Circular_kernel_3/demo/Circular_kernel_3/CMakeLists.txt
index 904cdf884d5..5cd80fabca5 100644
--- a/Circular_kernel_3/demo/Circular_kernel_3/CMakeLists.txt
+++ b/Circular_kernel_3/demo/Circular_kernel_3/CMakeLists.txt
@@ -5,7 +5,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 include(${CGAL_USE_FILE})
 
 find_package(Qt5 COMPONENTS Xml Script OpenGL)
diff --git a/GraphicsView/demo/Apollonius_graph_2/CMakeLists.txt b/GraphicsView/demo/Apollonius_graph_2/CMakeLists.txt
index 19cedbca651..40e1b7aaa50 100644
--- a/GraphicsView/demo/Apollonius_graph_2/CMakeLists.txt
+++ b/GraphicsView/demo/Apollonius_graph_2/CMakeLists.txt
@@ -8,7 +8,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 
 include(${CGAL_USE_FILE})
 
diff --git a/GraphicsView/demo/Bounding_volumes/CMakeLists.txt b/GraphicsView/demo/Bounding_volumes/CMakeLists.txt
index 96a66b26b24..2fca55bbab5 100644
--- a/GraphicsView/demo/Bounding_volumes/CMakeLists.txt
+++ b/GraphicsView/demo/Bounding_volumes/CMakeLists.txt
@@ -8,7 +8,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 
 include(${CGAL_USE_FILE})
 
diff --git a/GraphicsView/demo/Circular_kernel_2/CMakeLists.txt b/GraphicsView/demo/Circular_kernel_2/CMakeLists.txt
index 44dda726de6..1b0ed1f9cec 100644
--- a/GraphicsView/demo/Circular_kernel_2/CMakeLists.txt
+++ b/GraphicsView/demo/Circular_kernel_2/CMakeLists.txt
@@ -8,7 +8,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 
 include(${CGAL_USE_FILE})
 
diff --git a/GraphicsView/demo/Generator/CMakeLists.txt b/GraphicsView/demo/Generator/CMakeLists.txt
index 0cd2a1a666f..4dd0cbb5141 100644
--- a/GraphicsView/demo/Generator/CMakeLists.txt
+++ b/GraphicsView/demo/Generator/CMakeLists.txt
@@ -8,7 +8,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 
 include(${CGAL_USE_FILE})
 
diff --git a/GraphicsView/demo/GraphicsView/CMakeLists.txt b/GraphicsView/demo/GraphicsView/CMakeLists.txt
index 958b3d309f2..019c5069372 100644
--- a/GraphicsView/demo/GraphicsView/CMakeLists.txt
+++ b/GraphicsView/demo/GraphicsView/CMakeLists.txt
@@ -7,7 +7,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 
 include(${CGAL_USE_FILE})
 
diff --git a/GraphicsView/demo/L1_Voronoi_diagram_2/CMakeLists.txt b/GraphicsView/demo/L1_Voronoi_diagram_2/CMakeLists.txt
index a89f618a5e5..a83aaa8ad11 100644
--- a/GraphicsView/demo/L1_Voronoi_diagram_2/CMakeLists.txt
+++ b/GraphicsView/demo/L1_Voronoi_diagram_2/CMakeLists.txt
@@ -8,7 +8,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 
 include(${CGAL_USE_FILE})
 
diff --git a/GraphicsView/demo/Largest_empty_rect_2/CMakeLists.txt b/GraphicsView/demo/Largest_empty_rect_2/CMakeLists.txt
index 90bd8bf9b4f..5ae999b1233 100644
--- a/GraphicsView/demo/Largest_empty_rect_2/CMakeLists.txt
+++ b/GraphicsView/demo/Largest_empty_rect_2/CMakeLists.txt
@@ -8,7 +8,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 
 include(${CGAL_USE_FILE})
 
diff --git a/GraphicsView/demo/Periodic_2_triangulation_2/CMakeLists.txt b/GraphicsView/demo/Periodic_2_triangulation_2/CMakeLists.txt
index a5b4a6b7cd4..0ff9aa47646 100644
--- a/GraphicsView/demo/Periodic_2_triangulation_2/CMakeLists.txt
+++ b/GraphicsView/demo/Periodic_2_triangulation_2/CMakeLists.txt
@@ -8,7 +8,7 @@ if ( COMMAND cmake_policy )
   cmake_policy( SET CMP0003 NEW )
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5 REQUIRED)
+find_package(CGAL COMPONENTS Qt5)
 
 include(${CGAL_USE_FILE})
 
diff --git a/GraphicsView/demo/Polygon/CMakeLists.txt b/GraphicsView/demo/Polygon/CMakeLists.txt
index 71f0ef04ed8..e256f6b8fcc 100644
--- a/GraphicsView/demo/Polygon/CMakeLists.txt
+++ b/GraphicsView/demo/Polygon/CMakeLists.txt
@@ -8,7 +8,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5 Core)
+find_package(CGAL COMPONENTS Qt5 Core)
 
 include(${CGAL_USE_FILE})
 
diff --git a/GraphicsView/demo/Snap_rounding_2/CMakeLists.txt b/GraphicsView/demo/Snap_rounding_2/CMakeLists.txt
index 92e68483144..f8da80c9149 100644
--- a/GraphicsView/demo/Snap_rounding_2/CMakeLists.txt
+++ b/GraphicsView/demo/Snap_rounding_2/CMakeLists.txt
@@ -8,7 +8,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 
 include(${CGAL_USE_FILE})
 
diff --git a/GraphicsView/demo/Spatial_searching_2/CMakeLists.txt b/GraphicsView/demo/Spatial_searching_2/CMakeLists.txt
index a1f67366acd..3a1c7d76872 100644
--- a/GraphicsView/demo/Spatial_searching_2/CMakeLists.txt
+++ b/GraphicsView/demo/Spatial_searching_2/CMakeLists.txt
@@ -8,7 +8,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 
 include(${CGAL_USE_FILE})
 
diff --git a/GraphicsView/demo/Stream_lines_2/CMakeLists.txt b/GraphicsView/demo/Stream_lines_2/CMakeLists.txt
index 2bf2536acf7..c1881ef6ed5 100644
--- a/GraphicsView/demo/Stream_lines_2/CMakeLists.txt
+++ b/GraphicsView/demo/Stream_lines_2/CMakeLists.txt
@@ -8,7 +8,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 
 include(${CGAL_USE_FILE})
 
diff --git a/GraphicsView/demo/Triangulation_2/CMakeLists.txt b/GraphicsView/demo/Triangulation_2/CMakeLists.txt
index 7f83e32453d..30a921133ae 100644
--- a/GraphicsView/demo/Triangulation_2/CMakeLists.txt
+++ b/GraphicsView/demo/Triangulation_2/CMakeLists.txt
@@ -8,7 +8,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 
 include(${CGAL_USE_FILE})
 
diff --git a/Linear_cell_complex/demo/Linear_cell_complex/CMakeLists.txt b/Linear_cell_complex/demo/Linear_cell_complex/CMakeLists.txt
index 13825656b9e..17f59cfcea4 100644
--- a/Linear_cell_complex/demo/Linear_cell_complex/CMakeLists.txt
+++ b/Linear_cell_complex/demo/Linear_cell_complex/CMakeLists.txt
@@ -30,7 +30,7 @@ endif()
 add_definitions(-DCGAL_PROFILE_LCC_DEMO)
 
 ##################
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 include(${CGAL_USE_FILE})
 
 find_package(Qt5 COMPONENTS Xml Script OpenGL)
diff --git a/Mesh_3/demo/Mesh_3/implicit_functions/CMakeLists.txt b/Mesh_3/demo/Mesh_3/implicit_functions/CMakeLists.txt
index 8e8f42de751..2e1ab09d1eb 100644
--- a/Mesh_3/demo/Mesh_3/implicit_functions/CMakeLists.txt
+++ b/Mesh_3/demo/Mesh_3/implicit_functions/CMakeLists.txt
@@ -14,7 +14,7 @@ set(CMAKE_LIBRARY_OUTPUT_DIRECTORY "${CMAKE_RUNTIME_OUTPUT_DIRECTORY}")
 include_directories( BEFORE ${Mesh_3_implicit_functions_BINARY_DIR} ../include )
 
 # Find CGAL and CGAL Qt5
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 include( ${CGAL_USE_FILE} )
 
 # Find Qt5 itself
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 603bbde8ba5..aa45255751d 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
@@ -10,7 +10,7 @@ if(POLICY CMP0043)
 endif()
 
 # Find CGAL
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 include( ${CGAL_USE_FILE} )
 
 # Find Qt5 itself
diff --git a/Periodic_3_triangulation_3/demo/Periodic_Lloyd_3/CMakeLists.txt b/Periodic_3_triangulation_3/demo/Periodic_Lloyd_3/CMakeLists.txt
index 77ad080102d..a1cc8f4e53d 100644
--- a/Periodic_3_triangulation_3/demo/Periodic_Lloyd_3/CMakeLists.txt
+++ b/Periodic_3_triangulation_3/demo/Periodic_Lloyd_3/CMakeLists.txt
@@ -12,7 +12,7 @@ if(POLICY CMP0043)
   cmake_policy(SET CMP0043 OLD)
 endif()
 
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 include(${CGAL_USE_FILE})
 
 
diff --git a/Polyhedron/demo/Polyhedron/CMakeLists.txt b/Polyhedron/demo/Polyhedron/CMakeLists.txt
index 971ff57d8bc..1bab8434753 100644
--- a/Polyhedron/demo/Polyhedron/CMakeLists.txt
+++ b/Polyhedron/demo/Polyhedron/CMakeLists.txt
@@ -53,7 +53,7 @@ set( QT_USE_QTOPENGL  TRUE )
 if( POLYHEDRON_QTSCRIPT_DEBUGGER)
   set( QT_USE_QTSCRIPTTOOLS  TRUE )
 endif()
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 include( ${CGAL_USE_FILE} )
 find_package(Qt5 COMPONENTS OpenGL Script Svg Xml ScriptTools)
 
diff --git a/Principal_component_analysis/demo/Principal_component_analysis/CMakeLists.txt b/Principal_component_analysis/demo/Principal_component_analysis/CMakeLists.txt
index 60d65657f80..dc03be3282f 100644
--- a/Principal_component_analysis/demo/Principal_component_analysis/CMakeLists.txt
+++ b/Principal_component_analysis/demo/Principal_component_analysis/CMakeLists.txt
@@ -16,7 +16,7 @@ endforeach()
 include_directories( ./ )
 
 # Find CGAL and CGAL Qt5
-find_package(CGAL REQUIRED COMPONENTS Qt5)
+find_package(CGAL COMPONENTS Qt5)
 include( ${CGAL_USE_FILE} )
 
 # Find Qt5 itself