For some reason, it is a perfectly normal, well-adjusted behavior for a dog to love to roll in things like dead animals, manure, and garbage. Some behaviorists think this is an instinct which lets them cover up their own scent while hunting for prey. The only sure-fire way to prevent your dog from doing this is to not give him the option. This may be easy as far as the garbage is concerned, but not easy if you like to walk your dog in the countryside and let him off his leash. The most effective way is to train him effectively to listen to commands and be rewarded for obeying them.

Having said that, should the temptation to roll in something smelly be just to much to bother following commands, he can at least learn that if he does this he will not be allowed in the house or to jump up on you. At least this way he isn’t sharing his smell with you!