No, I don't think it is a css issue. The error is not present in the generated HTML. Here is what I am doing: 1) Set beRequired on MAAddressModel>>descriptionStreet 2) Go to the personeditor 3) Click on the create button for Home Address 4) Click the Save button (without entering any data). What I see when I do this is: • First Name: Input is required but no input given • Last Name: Input is required but no input given • Email: Input is required but no input given But there is no error for Home Address:, Street:. Looking at the html, Street does have the 'required' class, but it doesn't have the 'error' class and there is no error message for Street. My guess is that the problem has to do with the fact that Home Address is an MAToOneRelationDescription and some piece of code somewhere isn't recursing down into its constraints and errors. David On Jan 6, 2009, at 12:06 AM, Lukas Renggli wrote: