12 years ago we held a meeting in CASA on Cellular Automata Models. David O’Sullivan and Paul Torrens, both PhD students at the time – in fact David had finished and it was just before he went to Penn State – wrote a short editorial for Environment and Planning B on the state of the art of CA. We though the CAMUSS meeting would be a good opportunity to revisit the sate of the art and this morning (November 10th) yours truly is designated to present this. If you click on the various links here you will get the pdf. My view is still much the same as it was – that Urban CA tend to be more pedagogic devices than policy based models and that their theory is not very rich in terms of the way they articular the urban system. But there has been progress of sort and in the pdf, I recount some of this. We will write it up doubtless after the meeting.