This article outlines the assessment and quantifica tion procedures involved in determining the goodnessof-fit (congruence) between persons and their environ ments. A three-step procedure is outlined that includes (a) assessing a person's behavioral capabilities on a series of either community living or vocational skills, (b) determining the performance requirements within the person's respective living or work environments, and (c) computing a Goodness-of-Fit Index (GOFI) that quan tifies the congruence. Concurrent validity and correla tional data are presented that summarize the relation ship among criterion groups, GOFIs, and a number of outcome measures. This article concludes with a discus sion of potential uses of the GOFI procedure for com pleting discrepancy analyses, person-and setting-inter vention strategies, and formulating program develop ment and evaluation strategies.Recent studies have indicated that the successful adjustment of people with disabilities to their environ ments is related to both person-specific behavioral ca pabilities and setting-specific performance require ments (Landesman-Dwyer, 1981;Schalock, Gadwood, & Perry, 1984;Wilier & Intagliata, 1984). These results are consistent with a social ecological model which proposes that a person's successful adjustment depends on both the measurement and programming of personand setting-specific factors, and the facilitation of the congruence between persons and their environments (Romer & Heller, 1983).The present article focuses on one approach to operationalizing the social-ecology model. This article summarizes how one might assess the goodness-of-fit (congruence) between a person's behavioral capabilities and setting-specific performance requirements. Once assessed, these data can be used for a number of pur poses, including providing an index of important matched and mismatched skills; quantifying the con gruence for planning, monitoring, and evaluation purRequests for reprints should be sent to Robert L. Schalock,