Over the past 20 years, much exciting addiction research has been conducted. Extensive knowledge has been gathered about comorbid issues, particularly mental health disorders, HIV, and criminal justice involvement. Health services addiction research has become increasingly sophisticated, shifting its focus from patients to consider also services, organizations, and financing structures. Furthermore, through several long-term follow-up studies, empirical evidence convincingly demonstrates that drug dependence is not an acute disorder, and is best understood through a life course perspective with an emphasis on chronicity. This article highlights three major directions for future addiction research: developing strategies for chronic care (including longitudinal intervention studies), furthering cross-system linkage and coordination, and utilizing innovative methods (e.g., growth curve modeling, longitudinal mixed methods research) to strengthen the evidence base for the life course perspective on drug addiction.