One of the ways you can cut down on this misuse of your assets is to set up what is called a geofence. A geofence is a boundary you can set around a certain area by creating a perimeter of GPS points. If these points are ever crossed, you will be notified of the perimeter breach so you can take appropriate action.
An area out of your control that a geofence could help with its theft. If your driver is stopped for an extended period and is not set to drive again until a certain time, you can add a geofence around the vehicle. In the event this vehicle leave the perimeter before that designated time, you will be notified right away, allowing you ample time to seek help from law enforcement.