JOHN E. DOUGLAS has been an FBI agent for over thirty years. One of the most successful and best-known true crime authors in the country, his many books include the New York Times bestseller Mind Hunter, which first introduced the public to the idea of psychological profiles as a tool in hunting down killers.

ANN W. BURGESS, RN, DNSc, is the author of nine textbooks on psychiatric nursing and crisis intervention and ten books on assessment and treatment of child, adolescent, and adult sexual assault victims and serial offenders.

ALLEN G. BURGESS is a former associate professor in the College of Business Administration at Northeastern University in Boston.

ROBERT K. RESSLER, MS, is a twenty-year veteran of the FBI. He developed many of the programs that led to the formulation of the FBI's National Center for the Analysis of Violent Crime.