I know quite a few people that use the gentle leader on small breeds. Most of them seem to be pretty happy with it. There are the occassional ones that don't like the idea because their dog goes a little crazy at first. Give it some time, let the dog get used to it, give the dog a lot of commands and reinforcement while using it and be patient. It's a great product for just about any size of dog!
Another thing you could try is something called an Easy Walk harness. I had one for Maggie and they do work really well. They are easy to put on and no adjustment period that you would have when you first use a gentle leader since it fits the same as a harness would. The leash clips to the front of the harness so if they try to pull it turns their body around towards you. I work as a dog walker and trying to get a small gentle leader on a small dog especially one with long fur can be a real challenge. Here's their link http://www.premier.com/pages.cfm?id=74
***Edited By: Keesha63 on 12/29/2006 8:39:32 PM*** Reason: add