Over the past decade, the number of clinical trials registered with the Food and Drug Administration (FDA) has increased dramatically. The business of clinical research has become more diverse, involving academic institutions, clinician-researchers in community settings, pharmaceutical companies, and contract research organizations. This growth has been accompanied by increasing concerns about the ethical conduct of research. Much of this concern has been directed to procedural issues including institutional review board (IRB) review, data monitoring, and informed consent forms. However, the protection of human subjects cannot be achieved by relying solely on procedural safeguards. There are more nuanced issues related to recruitment and retention of subjects, and to the process of informed consent, that are generated during the interaction between study staff and subjects. It is only through an examination of these relationships that one can more fully define and understand the challenges of protecting subjects in research.