I have created a project in XCode and then created a User model with a firstName and lastName properties (strings). Then I go to my nib (xib actually) and add an ArrayController and set the mode to Entity and the EntityName to User to use my user model. I check the Prepares Content and Editable check boxes. The app will run at this point, but doesn't do much yet. But then I try to set the Managed Object Context and bind to File's Owner and set Model Key Path to managedObjectContext. Once I do this, the app no longer runs... it just bounces in the dock. I am following the directions from a tutorial so I think I am doing this right. Can anyone please help? Thanks....