The NYS involved a longitudinal study of a national probability sample of 1,725 youth between 11 and 17 years of age in 1976. Nine waves of data are available on this youth panel which was between 27 and 33 years of age when last interviewed in 1993. Both self-report and official record data are available for all respondents and their parents or primary caretakers. An analysis of self-report measures of violent behavior and the prevalence of serious violent offending indicates that individual offending rates and offense patterns in the youth panel compare favorably with those for incarcerated or arrested samples of violent offenders. The picture of serious violent careers that emerges from the self-report analysis differs in several respects from that derived from official record studies. The prevalence of serious violent offenses is substantially higher, onset occurs much earlier, demographic correlates are substantially weaker, evidence for escalation in offense frequency and seriousness is much stronger, evidence for the sequencing of serious forms of violent behavior is stronger, and the continuity of serious violent offending from juvenile into adult years is similar for males and females. General progression patterns involve offense diversification rather than offense specialization. Data show that 25 percent of males at age 17 are involved in some form of serious violent offending. 26 references, 10 footnotes, 1 table, and 7 figures