Who are the men committing the rising number of serial homicides in the U.S. -- and why do they kill? The increase in these violent crimes over the past decade has created an urgent need for more and better information about these men: their crime scene patterns, violent acts, and above all, their motivations for committing these shocking and repetitive murders.

This authoritative book represents the data, findings, and implications of a long-term F.B.I.-sponsored study of serial sex killers. Specially trained F.B.I. agents examined thirty-six convicted, incarcerated sexual murderers to...