The concept of "failure" in the context of interventions with substance users raises a number of issues that frequently are not applied to interventions with individuals suffering from other chronic diseases. Two of them have posed particular challenges for drug treatment courts: (1) the definition of failure; and (2) attributing the causes of failure. The author explores the ramifications of attempting to deal with these issues from both a criminal justice system and public health perspective--the two core disciplines working together to provide foundational support for Drug Treatment Court programs.