The career perspective examines substance use and abuse as an evolving sequence over time. From a career point of view, substance use is not just the use of a substance. It spreads across various stages along with specific use career pathways. Substance users are not just users of a common identity. They differentiate into various roles or statuses through individual use careers. Specifically, the career perspective (a) emphasizes the changing character of substance use and substance users, (b) stresses the accumulative effect of use or non-use episodes over a developing sequence of progression or regression, and (c) attends to the interaction of user characteristics, substance factors, and social influences through an evolutionary process. The career perspective, as a theoretical model, a methodological device, and a policy guide, has various implications for public health, social control, community, and organizational reactions to the problem of substance use and abuse.