Cate training is not something you HAVE to do... But the crate has a door that provides you the opportunity to practice. So... When you start practicing with your front door you are set up for success, by having established the rules already. Crates should not be used as punishment ( very important). Crates should be used for training and to control your dog's time so they don't learn to do wrong things. Keep in mind also, it is important for you to reward for going in and coming out when starting.