The conventional thought among law enforcement members, academic researchers, and profilers is that serial killers are generally White males in their 20’s or 30’s who are of above average intelligence and primarily kill strangers within their own race. The current study attempts to validate these hypotheses through an examination of 21 serial killers and their 97 victims. The cases were drawn from 15 jurisdictions and all cases have been closed by arrest and finalized through court processes. Data were drawn from police offense reports; investigative reports; crime scene photographs; videos and maps; transcripts of interviews with witnesses, surviving victims, relatives, and offenders; physical evidence examination reports; laboratory and forensic analysis reports; autopsy reports; criminal and prison records; and psychological profiles and psychiatric evaluations. The analysis indicated that although the conventional thought on serial killers generally holds true, there is more diversity among serial killers than had been previously believed. Most serial killers have no mental disorder and seem to understand the consequences of their actions. General characteristics of the sample in terms of demographics, relationship to victim, marital status, education, military service, and psychiatric diagnosis are described. The apprehension and punishment of serial killers is vitally important and, as such, preventative studies directed toward potential offenders should be encouraged. Tables, references