The latent trait model suggests that although actual involvement in criminal behavior decreases with advancing age, there is no substantial change in the underlying propensity of individuals to be more or less crime-prone. The life-course model recognizes that individuals commit fewer crimes as they age. The longitudinal research was based on two samples of respondents who were differentially involved in delinquency as teenagers: a sample of individuals living in private households, and a sample of previously institutionalized offenders. The data showed that prior delinquency was a stable predictor among respondents in both household and institutional samples. Although social bonding had a substantial impact on continued criminality among the household respondents, its influence was minimal among those who were previously institutionalized. The data suggested that the bonding levels and antisocial behavior of serious offenders were more resistant to change than were those of more typical and less serious offenders. The data for the household respondents provided support for both the latent trait and life-course models. Support for both theories was not as evident among the institutional respondents. It would be instructive to follow the respondents, particularly those still involved in significant antisocial behavior as young adults, even further into adulthood to gauge the persistence of their antisocial activities over the longer term. 4 tables, 6 notes, 43 references, and 1 appendix.