Originally Posted by lkenny
Whenever he would pull I would stop walking and he'd have to sit down and wait until I started to walk again. It seems now however that he has learned to slip both his harness and his collar. He will put his head down and his front legs together and let it slide off. Does anyone have a better harness/collar that is hard for them to slip off?
Take a look at the Freedom Harness by No Pull Harness | Designer Dog Collars | Wiggles Wags & Whiskers
It is a no pull harness but has an additional strap between the legs that most front-clip harness don't have. Additionally, it has a limited-slip loop on the back that will prevent the dog from slipping out backwards. If you use it with a double ended leash (they sell matching ones on the site) you get great control and lovely leash behavior from the dog.
If he is slipping his collar, the collar is too loose. You should only be able to slide two fingers under his collar otherwise you need to tighten it up. I prefer martingale collars (also called limited-slip collars or greyhound collars) because you can have them loose enough to be comfortable and lie nice on the neck, but they tighten a limited but effective amount when the dog pulls so that the dog can't slip the collar.