Nordic crime research is globally influential because it makes use of powerful register data. The main limitation of register data is its lack of important childhood psychosocial and environmental predictors of crime. The proposed project overcomes the register-only limitation through an analysis of the Stockholm Life-Course Project (SLCP), a longitudinal study of crime that includes childhood interview data. The SLCP shares features with seminal studies on the development of crime over life. The proposed project goes beyond those seminal studies by analyzing both crime and victimization across life. This project includes four studies. Study 1 determines how victimization and offending are related across life. The study also determines the extent to which the childhood environment can predict and distinguish between victims, offenders, and people who are both victims and offenders. A discordant sibling design is used. Study 2 determines whether most crime and victimization events are experienced by a “vital few”, and whether childhood environmental and psychosocial factors can be used to predict the vital few. Study 3 determines the impact of low self-control on offending and victimization across life. Multigenerational effects are tested. Study 4 determines the effect of parental monitoring on offending and victimization across life. Participants are matched with siblings to analyze familial concordance of offending and victimization.