diff --git a/lib/safe_yaml/parse/date.rb b/lib/safe_yaml/parse/date.rb
index cd3c62a..3a30a8b 100644
--- a/lib/safe_yaml/parse/date.rb
+++ b/lib/safe_yaml/parse/date.rb
@@ -1,3 +1,5 @@
+require 'time'
+
 module SafeYAML
   class Parse
     class Date