OBJECTIVES: To identify barriers and motivators to participation in long-term clinical research by high-risk elderly people and to develop procedures to maximize recruitment and retention. DESIGN: Quantitative and qualitative survey. SETTING: Academic primary care medicine and pre-anesthesia testing clinics. PARTICIPANTS: Fifty patients aged 70 and older, including 25 medical patients at high risk of hospitalization and 25 patients with planned major surgery. MEASUREMENTS: Fifteen- to 20-minute interviews involved open- and closed-ended questions guided by an in-depth script. Two planned study protocols were presented to each participant. Both involved serial neuropsychological assessments, blood testing, and magnetic resonance brain imaging (MRI); one added lumbar puncture (LP). Participants were asked whether they would be willing to participate in these protocols, rated barriers and incentives to participation, and were probed with open-ended questions. RESULTS: Of 50 participants (average age 78, 44% male, 40% nonwhite), 32 (64%) expressed willingness to participate in the LP-containing protocol, with LP cited as the strongest disincentive. Thirty-eight (76%) expressed willingness to participate in the protocol without LP, with phlebotomy and long interviews cited as the strongest disincentives. Altruism was a strong motivator for participation, whereas transportation was a major barrier. Study visits at home, flexible appointment times, assessments shorter than 75 minutes, and providing transportation and free parking were strategies developed to maximize study participation. CONCLUSION: Vulnerable elderly people expressed a high rate of willingness to participate in an 18-month prospective study. Participants identified incentives and barriers that enabled investigators to develop procedures to maximize recruitment and retention.