Data obtained about all persons known to have engaged in assassination-type behaviors directed at prominent public officials in the United States since 1949 indicate assassinations and attacks on public officials result from an understandable and discernible process of thinking and behavior. There are no accurate descriptive or psychological profiles of assassins; such individuals are both male and female and range across ages, educational backgrounds, employment histories, marital status, and other demographic and background characteristics. Persons who have attacked or come close to attacking public officials often exhibit attack-related behaviors. More than 40 percent of these persons have had an interest in assassination before they attacked or approached their targets. Assassins generally let others know about their intentions, use a range of planning strategies, behave quite rationally most of the time, are frequently interested in radical or militant groups, and usually attack after a downward spiral in their lives. Implications of the findings for law enforcement and security professionals involved in preventing attacks on public officials are discussed. References and footnotes