diff --git a/lib/xcodeproj/project/object/root_object.rb b/lib/xcodeproj/project/object/root_object.rb
index 8737400f..c6b50e59 100644
--- a/lib/xcodeproj/project/object/root_object.rb
+++ b/lib/xcodeproj/project/object/root_object.rb
@@ -53,6 +53,10 @@ class PBXProject < AbstractObject
         #
         attribute :minimized_project_reference_proxies, String, '0'
 
+        #  @return [String] preferred project object version
+        #
+        attribute :preferred_project_object_version, String, '73'
+
         # @return [PBXGroup] the group containing the references to products of
         #         the project.
         #
diff --git a/spec/project/object/root_object_spec.rb b/spec/project/object/root_object_spec.rb
index 45493fda..a656b8e8 100644
--- a/spec/project/object/root_object_spec.rb
+++ b/spec/project/object/root_object_spec.rb
@@ -43,6 +43,10 @@ module ProjectSpecs
       @root_object.minimized_project_reference_proxies.should == '0'
     end
 
+    it 'returns the preferred project object version' do
+      @root_object.preferred_project_object_version.should == '73'
+    end
+
     it 'returns the products group' do
       @root_object.product_ref_group.class.should == PBXGroup
     end