From the Introduction:
Mutt Movers is the role-playing game of moving mutts across the country from high kill shelters to rescue groups in areas where the dogs are in greater demand and likely to be adopted by families. The moves are coordinated by a monitor who typically supervises a number of drivers transporting mutts along a fixed route. Most of these start early in the day and rely on drivers who typically drive about one hour, then meet the next driver. They let the dogs take a water and potty break, then load them up in the next car headed for the rescue.
In this game, players can take on the role of mutts (all dogs on a move are called mutts regardless of their breed) or movers (the drivers who are helping to take dogs to a forever home). The game can be played with or without a Control. While the normal role of the Control on a mutt move is to keep drivers informed of the schedule, in the game Control is the person who generates the non-player participants in the move, both mutts and movers, and breathes life into them.
The object of the game is to achieve your character goal, which for most players will be to arrive at the destination rescue with all the mutts still in good health. This is how it nearly always goes in real-life, but of course there has to be more drama in the game or it will lose a lot of tension and probably fun.