Explaining the use of overlay methodology in the assessment of rural social service this paper describes a technique of visual juxtaposition wherein information is matched with geographic location. To ascertain whether senior citizen centers are located in areas of client concentration, for example, this model superimposes the location of senior citizen centers on the actual distribution of persons aged 65 and over. Presenting an example of the overlay technique as applied to a national study of quality of life involving nine indexes, this paper includes graphic illustrations of the technique. A further example of this technique as applied to a rural development project in Clinton County, New York is presented to illustrate the way in which four major phases of investigation (census and background data, crossroads survey, key informant survey, and general sample survey) can be compared via the overlay method. On the basis of the work presented in this paper, the following recommendations for assessing rural service needs are made: (1) assemble all pertinent census and secondary data; (2) map the data by geographic location; (3) conduct a windshield survey to identify actual locations of services; (4) interview key informants about where local residents go for services and what particular services are needed; (5) assemble all the data on overlay maps and present to local decision makers. (JC)