Just keyboard

*edit*
to be more specific, the controls are rather basic. There's a button for attack, jump/brake, enter/exit vehicle, next weapon, prev. weapon, and special (things like turning a police siren on and off or shooting water from a firetruck hose).

The movement controls are probably the hardest thing to get used to. The arrow keys are not directional. For example, if I press the up arrow, my player moves forward. if I press left or right, I turn. It's a little difficult to orientate yourself at first, but you get the hang of it.

Frankly, the downside of playing this game on modern computers is that now I can play the game at full speed, and man is that fast! I purposefully steal taxis now because they are relatively slow. If I hop in a Stinger or a police car, driving through traffic is litterally a hit and miss operation!