Physical aggression is typically attributed to inadequate control. While this is the pattern in 1 type of physically aggressive person, it is proposed that in another type, the Chronically Overcontrolled, rigid inhibitions against overt aggressive behavior will be found. Aggression by such people is apt to be of murderous intensity as aggressive impulse must build up to higher levels to overcome such inhibitions and since alternative means of expressing aggression have not been learned. This suggests that in comparison with other criminal groups, a murderously assaultive group will be assessed as l ess hostile, l ess aggressive, and more controlled. An empirical study of 4 groups of assaultive and nonviolent delinquents supports this prediction. Implications of this finding for practice and theory are discussed.Aggression and violence are more than ever becoming major problems in the United States. The names of Los Angeles, Rochester, and St. Augustine have joined Bunker Hill, Gettysburg, and the Little Big Horn as American battlegrounds, There is also concern regarding individual violence. In a single week a national magazine reported the cases of two 22-year-old boys, one (a "gentle, easy-going, good natured" young man) who 5 days after graduation killed three unarmed victims during a bank robbery and the other (a "mild and loving" person) who shot his twin brother {Newsweek, 1965).When we try to apply information gleaned from empirical studies of aggression to events such as these we find a great gap between the aggression described in our journals and that described in our news-1 Based on a doctoral dissertation submitted to the Department of Psychology at the University of California, Berkeley. The author wishes to express his appreciation to the members of his doctoral committee, Hubert Coffey and Irving Piliavin, and, most especially, to the chairman, Gerald A. Mendelsohn, for assistance in the design, execution, and interpretation of the study. He also wishes to thank Lorenzo S. Buckley, Chief Probation Officer of Alameda County, California, and the staffs of the Guidance Clinic and of Juvenile Hall who collected and transcribed the data. Finally, he wishes to thank the University of California Computer Center for donating time on the IBM 7090.2 Now at the University of Texas.