The aim of this survey was twofold: to assess the willingness of medical students to volunteer for clinical trials and to evaluate the weight of the financial reward and other general details as seen by healthy volunteers who had already participated in clinical trials. A specific questionnaire was given to each group to be answered anonymously. Among the medical students only 2.9% had already volunteered, 39.7% said that they would never participate, 24.7% would do it for scientific interest, 32.2% for scientific interest and financial reward, and 4.2% for the financial reward alone. In experienced volunteers, financial reward was the main reason to participate (90%) followed by curiosity (6.3%). The financial reward actually received was considered adequate compensation for the time and discomfort by most of the volunteers (83.7%). The information supplied by the research team and the arrangements made to treat any hazardous event were considered adequate (47.5%) or optimal (42.5%). Almost all the experienced volunteers (93.8%) answered positively when asked about participation in future studies. The results show that financial reward is a very important reason for healthy volunteers to participate in clinical trials.