Spectacular treatment disasters in recent years have made it clear that informal "let's-try-it-and-see" methods of testing new proposals are more risky now than ever before, and have led many to call for a halt to experimentation in clinical medicine. In this easy-tp-read, philosophical guide to human experimentation, William Silverman pleads for wider use of randomized clinical trials, citing many examples that show how careful trials can overturn preconceived or ill-conceived notions of a therapy's effectiveness and lead to a clearer understanding of clinical anomalies. Because it gives careful guidance on setting up trials and avoiding conceptual pitfalls, this book will be of great interest to all epidemiologists and clinical statisticians, and to a wide varitey of clinicians, pharmacologists, and nurses. Since it requires no medical or statistical knowledge, it will also appeal to ethicists, lawyers, and the general public.