This study has three objectives: (a) to compare socio-demographic characteristics of dropouts and completers of a health promotion program, (b) to assess each group's satisfaction with specific aspects of the program, and (c) to investigate the reasons for dropout. Data were collected by means of individual structured interviews with 19 dropouts and 20 completers randomly selected. Results show that the two groups do not differ on socio-demographic variables. Completers were significantly more satisfied than dropouts with only a few aspects of care. Investigating dropouts' motives added key information We conclude that useful measurement of patient satisfaction should focus on specific aspects of care and on survey dropouts as well as completers, and should assess dropouts' motives.