Hey MR, I've been puzzling myself over this problem for a month or two now, and after researching the problem on Google and other programming QA sites, I haven't managed to find the error. So my problem goes like so: I have a WindowController and ArrayController, both NSObjects. An NSTableView, with each of it's three columns bound to Key Paths and hooked up to the ArrayController. My program will use an external HTTP stream, and generate an NSMutableArray of NSMutableDictionary objects, which are then passed to the ArrayController. I can accurately generate the Dictionaries, and compile the Array of said dictionaries. The problem lies in why I cannot get it to visually display on the form. I'm literally at last-chance saloon with this error, and if I can save the project, i'd be eternally appreciative! I've uploaded the project to my webspace if anyone fancies a peek, or I can post some of the code when I know what will help. Thanks, Matt.