In order to determine the reliabilities of successful outcomes (or failures) from a complex which consists of two independent systems each containing a series of independent trials, the product of two binomial series may be employed. In practical problems, however, some qualifications and constraints are generally imposed which render this approach to the problem awkward and difficult. In this article a complex consisting of a missile system and an integral but independent telemetry system is considered in devising a method to determine these reliabilities. Results indicate that the reliability of telemetry reports is high even when the systems reliabilities are not particularly high.