Background: Older participants are often excluded from clinical trials, precluding a representative sample. Study Design: Using qualitative and quantitative methods, we examined recruitment and retention of older women with pelvic organ prolapse in two surgical trials: the randomized Colpopexy And Urinary Reduction Efforts (CARE) study and the Longitudinal Pelvic Symptoms and Patient Satisfaction After Colpocleisis cohort study. Using focus groups, we developed a questionnaire addressing factors facilitating and impeding the recruitment and retention of older study participants and administered it to research staff. Enrollment-to-surgery ratios, missed visit rates, and dropout rates for older and younger participants were compared using Fisher's exact test, with cut-points of 70 and 80 years for the CARE and Colpocleisis studies, respectively. Results: Questionnaires were completed by 23 physician investigators and 11 nurses or coordinators (92% response rate). Respondents indicated it was more difficult to recruit older research participants (32%), obtain informed consent (56%), and retain participants to study completion (50%). Challenges to recruitment included caregiver involvement in the decision to participate and participant comorbidities. Perceived barriers to retention were transportation, caregiver availability, and participant fatigue. Data quality was challenged by sensory and cognitive impairment, resulting in a change from telephone interviews to in-person visits in the Colpocleisis study. Older participants did not have higher dropout rates than younger participants. There were no differences in missed in-person visits or telephone interview rates between age groups. Conclusions: Strategies, albeit unstudied, could assist investigators in planning surgical trials that successfully enroll and retain older women. © 2008 American College of Surgeons.