This project integrates elements of responsive evaluation and participatory evaluation to compare three evaluation data collection methods for use with a hard-to-find (HTF), traumatized, vulnerable population: rape victims seeking postassault medical forensic care. The first method involves on-site, in-person data collection, immediately postservices; the second, telephone follow-up assessments, 1 week postservices; and the third, private, self-administered surveys completed immediately postservices. There are significant differences in response rates across methods: 88% in-person, 17% telephone, and 41% self-administered. Across all phases, clients gave positive feedback about the services they received and about all three methods of data collection. Follow-up analyses suggested that nonresponders did not differ with respect to client characteristics, assault characteristics, or nursing care provided. These findings suggest that evaluations with HTF service clients may need to be integrated into on-site services because other methods may not yield sufficient response rates. (Contains 2 tables and 2 notes.)