My cat wears a collar and a bell in the spring/early summer because there are some fairly rare birds up here on the farm and I feel mortified when she brings the chicks back! Otherwise, I don't bother usually. She is used to wearing a collar from an early age and doesn't seem to mind wearing it (I always give her a fuss when I've put it on her so she associates it with pleasure), though she managed to get rid of one I got with the snap off safety feature.