diff --git a/lib/bson/date.rb b/lib/bson/date.rb
index <HASH>..<HASH> 100644
--- a/lib/bson/date.rb
+++ b/lib/bson/date.rb
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+require 'date'
+
 module BSON
 
   # Injects behaviour for encoding date values to raw bytes as specified by
Require date to account for RubyGems <I> dropping dummy class