Doggles have adjustable straps at the bottom by the chin and on top of the head, behind the ears. BUT... if the chi is uncomfortable with it and tries to paw it off, it will come off. Other than that, it stays on. It sits pretty good on her muzzle. Fortunately, Hershey is used to it and wouldn't take it off 90% of the time. :coolwink:so cute. Do those sun glasses stay on?