Chasing

First determine if he is motivated by movement or fear of the object. Then determine the ‘What’ and ‘Why’. These will help you correct any underlying problems that may be working against you. The more you understand your dog’s motivations the easier it will be for you to establish new behavior patterns.

What? Cars, bikes, people, animals.
Why? Aggression, sport, fear, play, protection, instinct.

The method to correct the Chasing dog is similar to the one for Boundary Training.

Walk him on a long line toward the distraction that causes the chase. Set him up with the help of a friend if you have to. When he starts to chase, turn and walk away giving him a sharp tug. When he catches up to you, praise and give a treat (reward not bribe). Repeat until he looks at the distraction and then to you, without giving chase.

This is also considered a behavior modification exercise. You aren’t teaching him a command, rather a behavior pattern. It will take time and repetition. At least one - two months of regular, consistant work.