The reliability of a simple production-storage system in meeting a constant known demand at rate D is anlayzed. This system consists of a production facility subject to stochastic failure and repair processes and a storage facility of fixed capacity. When operable, the production facility is assume to produce at rate M > D until the storage facility is full and then at rate D. Expressions are developed for the fraction of time demand is met and the probability distribution of the contents of the storage facility.