Previous economic studies have examined the association between substance abuse treatment and reduced costs to society, but it remains uncertain whether the economic measures used in cost and benefit-cost analyses of treatment programs correspond in direction and magnitude with clinical outcomes. In response to this uncertainty, the present study analyzed a longitudinal data set of addiction treatment clients to determine the statistical agreement between clinical and economic outcomes over time. Data were collected from 1,326 clients in the Chicago cohort of the Persistent Effects of Treatment Study. These individuals were interviewed at baseline as well as at 6-, 24-, 36-, and 48-month followup periods (91.6% followup). Correlations between clinical and economic measures were generally small (rho of 0.1 to 0.3) and often became non-significant once we controlled for baseline severity. The results demonstrate that although some associations exist, outcomes should be evaluated along both clinical and economic dimensions.