Objectives: Stuttering has been associated with a range of anxiety disorders, including social phobia. In the general community, anxiety disorders are frequently associated with increased rates of mood and substance use disorders. Therefore, in the present study, the authors sought to determine the rate of mood and substance use disorders among adults who stutter. Method: The study employed a matched case-control design. Participants included 92 adults seeking treatment for stuttering and 920 age- and gender-matched controls. Mental health assessments were conducted via a computerized psychiatric diagnostic interview. Conditional logistic regression models were used to estimate odds ratios for the prevalence of mood and substance use disorders in both groups. Results: When compared with matched controls, adults seeking treatment for stuttering had twofold increased odds of meeting criteria for a 12-month diagnosis of any mood disorder but were not found to report significantly higher lifetime prevalence rates for any substance use disorder. Conclusions: Although adults who stutter in the present study were characterized by significantly higher rates of mood disorders than matched controls, they do not appear to self-medicate with substances such as alcohol. Results are discussed in terms of treatment implications and possible reasons why adults who stutter may avoid alcohol.