The software industry is painfully realizing that a software reuse effor~if not carefully planned and properly carried out, oftentimes becomes an inhibitor rather than a catalyst to software productivity and quality.Despite numerous articles in the areas of domain analysis, component classit3cation, automated component storage/retrieval tools, reuse metrics, etc., only a handful have managed to address the economics of software reuse.In order to be successful, not only must a reuse program be technically sound, itmust also be econondcally worthwhile.After all, reducing costs and increasing quality were the two main factors that drove software reuse into the software mainstream.This paper presents a number of reuse economics models used to perform an economic assessment of a reuse effort on a large-scale Ada projecti the United States Federal Aviation Administration's Advanced Automation System (FAA/AAS).Reuse economics models, cost/benefit tracking methods, and reuse catalysts/inhibitors are addressed.