Between Good and Evil: A Master Profiler's Hunt for Society's Most Violent Predators 
Roger L. Depue spent decades tracking down America's most depraved criminals. First as a small town police chief, then as a S.W.A.T. team member, and ultimately as head of the FBI's famed Behavioral Sciences Unit--the unit responsible for profiling and hunting serial killers--where he pioneered revolutionary law enforcement programs and techniques that remain in use today by the FBI and police departments across the globe. In his quest to comprehend the true nature of good and evil, Depue embarked on a mid-career spiritual sabbatical to become a Brother of the Missionaries of the Holy Apostles, counseling maximum security inmates. With his combined experiences as both a law enforcement professional and a member of the clergy, Depue explores the criminal mind and soul as no one has ever done before.
Reviews
Actual cases are used throughout the book, as well as some of his conclusions - eg. psychopaths tend to degenerate as the police close in (Bundy's final murders occurred as a rampage in a Florida sorority house, totally unlike his initial well-planned and conning cases), violent criminals have a common thread of child abuse and often head injury as well (though not all abusers become violent), "overkill" at a murder is a sign that the victim knew the perpetrator.
Depue was involved in the Martha Moxley murder case while a consultant, and his FBI staff interviewed a number of killers (including Ted Bundy) while developing their conclusions.
Depue is clearly a very skilled detective. However, the jury is still out on whether criminal profiling is useful. The research literature on the topic is limited and somewhat negative; in addition, more than one leading police official has declared that he knew of no instance where profiling led directly to apprehension (though it often confirms what is eventually found).