This document summarizes pneumatic process control. It discusses that pneumatic controls are powered by compressed air and are safer than electronic controls in explosive environments like chemical plants. It then describes the basic components of a closed-loop pneumatic control system including a controller, actuator and measuring device. Finally, it explains some common pneumatic control devices like flapper nozzles, volume boosters, and force balance transducers and how proportional and proportional-integral controllers work in pneumatic systems.