Between 6,000 and 8,000 sniping incidents occur yearly in the United States, and the incidence of sniping is increasing dramatically. Because of the sheer numbers of sniping incidents, most cases either go unreported or receive little attention from the press. This work documents major case histories which represent the different types of snipers and methods, including the juvenile vandal, the psychotic mass murderer, and the political terrorist. Most of the sniping incidents appear senseless, and since the criminal snipers have no particular type of personality there is no way to predict or isolate them before they act. For example, Charles Whitman, the sniper who killed 18 persons and wounded 30 from the tower on the University of Texas campus, appeared to be a stable honor student, although further investigation revealed his deep-seated hostilities and aggressiveness. Also described herein are the cases of Carmen Sherbeck and Fred Nocella, Son of Sam, and Mark Essex. The latter's case is a classic example of the hit and run sniper. Political murder, the ambush on de Gaulle, and revolutionary assassins are also discussed. It is suggested that the sniper, like any other type of criminal, exhibits patterns of behavior which must not be ignored. However, data for determining characteristics important for identifying the character or motive of the assailant are often overlooked by investigating personnel. Ways for categorizing and dealing with snipers are explored. (Author summary modified)