With my RIP Max, he use to always wear one. Then around age 5 it was choaking him when he would lay on his couch. It was bad enough that he barfed. I made the collar super loose & that didn't help at all. So I just kept it on the door knob for when we went for a walk (but I forgot it 99% of the time). He always had it for car rides, but it was never on him, it would be tossed on the seat, just incase we had to stop to let him tinkle in a strange area (he wouldn't run away but some places have tag rules).