diff --git a/chapter06/CMakeLists.txt b/chapter06/CMakeLists.txt
index e059086..655b5c7 100644
--- a/chapter06/CMakeLists.txt
+++ b/chapter06/CMakeLists.txt
@@ -4,7 +4,7 @@
 
 cmake_minimum_required(VERSION 3.23)
 
-option(ENABLE_DOCUMENTATION "Enable documentation" OFF)
+option(ENABLE_DOCUMENTATION "Enable documentation" ON)
 
 if(NOT ENABLE_DOCUMENTATION)
   message(STATUS "Documentation is disabled, excluded chapter 6 documentation examples")
diff --git a/chapter06/ex01_doxdocgen/CMakeLists.txt b/chapter06/ex01_doxdocgen/CMakeLists.txt
index 1b0c0a9..36071a2 100644
--- a/chapter06/ex01_doxdocgen/CMakeLists.txt
+++ b/chapter06/ex01_doxdocgen/CMakeLists.txt
@@ -30,7 +30,7 @@ set(DOXYGEN_AUTOLINK_SUPPORT YES)
 # Enable dot graph support
 set(DOXYGEN_HAVE_DOT YES)
 # Include collaboration diagrams in class documentation
-set(DOXYGEN_COLLABORATION_GRAPH NO)
+set(DOXYGEN_COLLABORATION_GRAPH YES)
 # Include class diagrams in class documentation
 set(DOXYGEN_CLASS_GRAPH YES)
 # Generate UML-like graphs
diff --git a/chapter07/CMakeLists.txt b/chapter07/CMakeLists.txt
index 87cf8a0..22c59a9 100644
--- a/chapter07/CMakeLists.txt
+++ b/chapter07/CMakeLists.txt
@@ -12,6 +12,8 @@ project(
     LANGUAGES CXX
 )
 
+include(CTest)
+
 add_subdirectory(simple_test)
 add_subdirectory(test_labels)
 add_subdirectory(pass_fail_criteria)