The conceptual tools used in the communication/language objectives-based system (C/LOBS), which supports the front-end analysis efforts of the Defense Language Institute Foreign Language Center, are examined. The C/LOBS project, which is described in 13 volumes and an executive summary, functions as a subsystem of the instructional systems development approach currently in use in the TRADOC school system. C/LOBS was designed to develop a systematic set of procedures for determining terminal skill objectives and their supporting enabling objectives for foreign language training. Five job/duty positions and three languages were selected for field testing and system validation. This volume presents an explanation of the functional system and how it fits with other system concepts, and some heuristics for its use; lists the functional categories and functions which were developed in the course of the project; and presents operational definitions for each function listed. It offers synonyms, a definition of the function, sample English utterances which are examples of the function, comments, and examples of function catalog entries. (SW)