You goal is to kill the convoys that are try to cross the bridge. You have to place the dynamite in the right place so that it will completely destroy the structure. No individual in the convoy can survive in order to complete the level. It will not always be so simple. In some levels you have to make sure the doctors survive. You will also have times when certain dynamite has to be placed in a specific place such as a rope that is holding half of the bridge up. You have limited dynamite so place them very strategically.