This paper reports on a formative research study designed to elicit preferences for STD/HIV prevention programs from clients at a mid-western STD clinic. Eleven dimensions defined the hypothetical program descriptions: (1) types of participants in the prevention program, (2) specific intervention content, (3) associated medical procedures, (4) design of the study in terms of sessions and follow-up data collection, (5) compensation for participation, (6) availability of child care, (7) race/ethnicity of the program staff, (8) gender of the intervention counselor, (9) location of the intervention programs, (10) source of the program staff, and (11) funding source for the project. Results showed that potential participants preferred mixed groups or meeting individually with a counselor, extensive intervention design/data collection options were less favored than single sessions, incentives help to increase participation, homogenous ethnicity of staff decreases participation while 'a mix of races and ethnicities' increases the odds of participation. Published by Elsevier Science Ltd.