The 25 self-reported delinquency measures used in this study included all Uniform Crime Report Part I offenses except homicide; 60 percent of all Part II offenses; and a wide range of other offenses, including delinquent lifestyle items, misdemeanors, and status offenses. Respondents were asked in structured interviews how many times during the past year they had committed each offense. Estimates are given for the total adolescent population and for subgroups defined by sex, social class, ethnicity, and age. The social class measure used is the Hollingshead index applied to the principal wage earner in each youth's family in order to divide them into three categories: (1) professionals or managers with college educations (23 percent); (2) owners of small businesses, salespersons, or skilled workers with high school or some college education (29 percent); and (3) persons in semiskilled or unskilled occupations (42 percent). Ethnic classifications were white, black, Hispanic, and others. Within the sample, 53.2 percent were male, 78.9 percent were white, and 15.1 percent were black. Separate statistical tables are presented for males, females, whites, blacks, other ethnic groups, each social class, and individual age groups. The methodology's validity is discussed, and 16 references are provided.