For the past 18 years Carleton Life Support Systems has produced over 15,000 tactical cryogenic coolers that are primarily used in military infrared systems with excellent demonstrated reliability. As system reliability has improved, the cooler performance has emerged as a dominant component for reliability predictions. This has driven cooler reliability requirements to increase from a 1500-hour rotary cooler in chiefly ground applications to current requirements of 20,000 hours for linear coolers in advanced airborne applications. At the same time there is a push for improved cooldown time, lower power, lighter weight and smaller package. This paper reviews our progress on extending cooler life. It reviews recent product returns and contends that the majority of issues are not primarily related to reliability. It also reviews how system performance specifications are restrictive to the cooler designer in achieving higher reliability in tactical coolers.