Linear-drive Stirling-cycle cryocoolers designed with non contacting parts are ideal for long-life cryogenic cooling applications. These cryocoolers are light weight, have an almost unbounded operational life, and require no expensive ground handling equipment or procedures. One of the challenges in applying these refrigerators to sensitive instruments is precision temperature control. Developing a closed loop temperature control system for a Stirling-cycle cryocooler has been a recent project at the Lockheed Research & Development Division.