Sherrow's biography of the scientist credited with developing a successful polio vaccine begins with some history of the disease and then follows Salk through his schooling and into the scientific laboratory. Salk's years of research and laboratory work, described in some detail, are the subject of several chapters. The last section explains the Salk Institute's recent work in researching cancer and AIDS. Notes at the end of each chapter indicate extensive use of primary source materials. A readable, inspiring portrait of a hero in the field of medical research.