INTRODUCTION

Experimentation on human beings may be as old as medicine itself. The search for new therapies – drugs, devices, and procedures – required that someone go first, some individual participate in the trial of an innovative treatment, and experience both the risks and benefits of that participation. Although these risks and benefits remain for research subjects, the norms governing research with human subjects, the understanding of the ethical responsibilities of investigators and the rights of research subjects has undergone a profound transformation over the course of the twentieth century. Once implicit and informal understandings of the limits of appropriate experimentation have become codified into federal regulations that require (in the United States) written and informed consent of participants and institutional review of the proposed research (see Chapter 50). Ethical issues in the use of human subjects remain (for example, the conduct of human research by Western investigators in developing countries, an issue intensified by the acquired immunodeficiency syndrome (AIDS) pandemic), but there are some legal protections for human subjects and more clearly defined responsibilities for individual researchers and their institutions (see Chapter 51).

Legal restrictions on the use of laboratory animals preceded legal protections for human subjects by decades or more (see Chapter 48). The moral status of animal experimentation remains, in many respects, more highly contested than human experimentation.