We check our cats often to make sure they are not tight. We also use the kind that "break away" if they get caught on something. Last night Max was out on the chain in the yard (I got him a harness but we do not like it... it's the figure 8 style?? And either it's too loose and comes off around his feet or too tight around the neck... Im getting him a new one this weekend in Canada) and a car drove by and he freaked... :/ he came in w/no collar on.... but it doesnt break super easily and I can snap it back on.