Brinkerhoff's Success Case Method (SCM) was developed with the specific purpose of assessing the impact of organizational interventions (e.g., training and coaching) on business goals by analyzing extreme groups using case study techniques and storytelling. As an efficient and cost-effective method of evaluative inquiry, SCM is attractive in other contexts as well, although few examples of such uses are to be found in the published literature. However, modifications of the SCM concept and design are sometimes necessary for implementing the approach in nonprofit environments where business goals are not necessarily an explicit objective. This method note demonstrates how SCM was modified and extended to a social service context, in which the program evaluated was aimed at reducing chronic homelessness and unemployment. Modifications included defining success in a nonprofit setting and adding a time-series element to the design features of traditional SCM to increase methodological rigor. (Contains 4 figures and 1 table.)