You can have an alarm type system installed. Experts suggest that you get the type that disable the starter preventing the car from being driven away. You might also want to have a 'kill switch' installed. This simple hidden device will not allow the engine to run unless it's in the 'on' position. Only you and the person who installed it will know it's location.
Many thieves take cars by using a 'hot wire' to bypass the ignition switch.
There are devices available that will shut off the fuel or ignition systems if a 'hot wire' is detected. Without gas or ignition the car won't go. On the high tech end are devices that can lead the police directly to your car if it's stolen. If your car is stolen a signal is sent to the car to activate the transmitter. You may not be able to completely eliminate the ability of crooks to take your car or truck.