COPIES OF THE OFFENSE REPORTS FOR EACH SAMPLED CASE WERE EXAMINED, TOGETHER WITH THE ARREST RECORDS OF BOTH OFFENDERS AND VICTIMS. THE CASES ARE ANALYZED IN TERMS OF THE TIME, LOCATION, AND SEASON OF YEAR; WEAPON; REPORTING; INJURY; POLICE PROCESSING; ALCOHOL INVOLVEMENT; VICTIM-OFFENDER RELATIONSHIP; AND ARREST RECORDS. THE ACT OF AGGRAVATED ASSAULT IS MOST LIKELY TO OCCUR ON A WEEKEND, PARTICULARLY ON SATURDAY BETWEEN 10:00 P.M. AND 11:00 P.M. ALTHOUGH THE FREQUENCY OF AGGRAVATED ASSAULT VARIES LITTLE BY SEASON, IT DOES PEAK IN JULY AND AUGUST. THE CRIME OCCURS MOST FREQUENTLY (1) ON A PUBLIC STREET OR (2) IN A RESIDENCE. THE KNIFE IS THE MOST LIKELY WEAPON TO BE INVOLVED. PERSONAL FORCE IS MORE COMMON IN ACTS INVOLVING WHITE OFFENDERS THAN IN ACTS INVOLVING BLACK OFFENDERS. GENERALLY THE ACT IS REPORTED TO THE POLICE BY THE VICTIM, WHO, UNLIKE THE OFFENDER, IS LIKELY TO BE WOUNDED SERIOUSLY ENOUGH TO REQUIRE HOSPITALIZATION. NEITHER THE VICTIM NOR THE OFFENDER IS LIKELY TO BE UNDER THE INFLUENCE OF ALCOHOL AT THE TIME OF THE ASSAULT. AGGRAVATED ASSAULT OFTEN IS PRECEDED BY A VERBAL ARGUMENT, MOST LIKELY CENTERING AROUND A DOMESTIC QUARREL. MOST OFTEN THE OFFENDER AND VICTIM ARE OF THE SAME RACE AND SEX, AND BOTH HAVE BEEN BORN OUTSIDE OF THE CITY IN WHICH THE CRIME OCCURS. BOTH ARE LIKELY TO BE IN THE SAME AGE GROUP, USUALLY BETWEEN THE AGES OF 20 AND 35. MOST OFFENDERS IN THE AGE GROUP 20 TO 34 HAVE A PRIOR ARREST RECORD. MORE SIMILARITIES THAN DIFFERENCES ARE FOUND WHEN THE ST. LOUIS DATA ON AGGRAVATED ASSAULT ARE COMPARED TO FINDINGS ON HOMICIDE IN PHILADELPHIA REPORTED IN A 1948-1952 STUDY. SUPPORTING TABULAR DATA ARE INCLUDED.