A new, more specific language for describing work activities, based upon the duty module (clusters of tasks that tend to go together occupationally and organizationally in meaningful ways) is being designed for the Army. The purpose is to improve communications between resource and requirement planners and program operators. The paper proposes two different kinds of modular evaluation devices: sets of tasks performed by individuals, and sets of tasks performed by organizational units. Most of the document examines and evaluates existing approaches to proficiency testing in the Armed Forces. Some duty modules are listed but the proposed designs have been neither analyzed nor evaluated. Recommendations are made for further development of the duty module concept. (NH)