Drawing on diverse approaches to the study of youth development and adult functioning, as well as social capital and citizenship, this investigation identifies measures of positive adult behavior. Although prevention researchers study protective factors, as well as risk factors, for problem behaviors and other negative outcomes, less attention is given to positive behavior outcomes and there is little understanding of the relationships between positive and negative outcomes. Analyses included 765 participants from the Seattle Social Development Project interviewed at age 21. Seven measures of positive adult behavior were identified: volunteerism, group involvement, neighborliness, interpersonal connection, constructive engagement, financial responsibility, and honesty. Measures related to distal social relationships (group involvement and neighborliness) had relatively weak associations with crime and substance use. In contrast, the measures of constructive engagement, financial responsibility, and honesty had significant negative associations with multiple measures of crime and substance use. Results indicate that the seven measures provide relatively independent variables useful for assessing positive adult behavior. These measures can be used to assess positive outcomes in adulthood of intervention studies, or to assess the prevalence of positive adult behavior in different populations or groups.