I cancelled a couple of times in the ten years with former T, once about an hour and a half before because I had gotten in a car accident and my car wouldn't go! But never too frequently that she charged. If for some reason I couldn't come she would generally try to get me a phone appointment to cover sometime that week. I have cancelled twice with current T. Once I just didn't feel like going (but I gave her a week's notice) and once I was going to be out of town, gave her two weeks notice that time.