Hi There! Usually when a normally behaved cat starts going outside the box, it is either due to a medical condition or a change in environment. I would suggest a trip to the vet to rule out anything medical first. If he gets a clean bill of health, consider if there have been any changes at all in his or your schedule, new furniture, pets, anything at all could set him off. If you think that this has been the result of a change or stressful event, you can add a Feliway Diffuser to the room he messes in. This emits a calming to the cat pheromone scent that will help him with this marking behavior. There are ways to deter him from his usual spot and get him back into the box. First, if you do not have 2 litter boxes, you might try adding one. Some cats decide that they do not like to poop where they pee, and be sure to scoop them daily. Add a product called Cat Attract to the box, as this has a very high success rate in getting him back in the box. To clean the area he has messed, use a good enzymatic cleaner such as Nature's Miracle. That will remove all traces of his smell and keep him from going back to it. I wish you the best of luck with this, please let me know how he does! Best Wishes, Reani
Cat Care Expert
20+ years experience with Cat Care and behavior problems, 3 years Pet Rescue