diff --git a/koans/path_to_enlightenment.rb b/koans/path_to_enlightenment.rb
index a36f237..6a87bcb 100644
--- a/koans/path_to_enlightenment.rb
+++ b/koans/path_to_enlightenment.rb
@@ -7,6 +7,7 @@ require 'about_array_assignment'
 require 'about_hashes'
 require 'about_strings'
 require 'about_methods'
+require 'about_constants'
 require 'about_control_statements'
 require 'about_true_and_false'
 require 'about_triangle_project'