This paper explores the relationships between the costs of developmental testing and the derived benefits in reliability. The analysis quantifies this relationship for the components of the dynamic system of a specific future helicopter. Distinctions are drawn between test costs related to reliability requirements and those that are not related. Emphasis is placed on the decisionmaking process that is required when formal reliability and maintainability (R&M) demonstration tests are imposed. The statistical aspects of demonstration tests are examined and related to the program manager's informational requirements.