Objective: The purpose of this study was to examine the psychopathological profile that may be associated with the retention of patients for 90 days in a therapeutic community. Method: In this study, we used a prospective longitudinal descriptive design. Participants were 218 cocaine-dependent individuals. Psychopathological assessment was performed using the Psychiatric Research Interview for Substance and Mental Disorders (PRISM) and Conners’ Adult ADHD Diagnostic Interview for DSM-IV (CAADID). The outcome measure was retention and was defined as the time in therapeutic community treatment (number of days), the type of discharge, and the clinical impression of the therapeutic outcome. Results: Of all patients, 68.3% (149) were stayers, and 31.7% (69) were dropouts after 3 months of treatment. In comparison with stayers, the dropout patients were in therapeutic community treatment fewer days, and they had a larger percentage of nonrelevant or minimal clinical changes at the end of the treatment (p < .001). Regarding the presence of other mental disorders, among the dropout patient group, the percentage of diagnostics is larger than in the stayer group. This difference is statistically significant for borderline personality disorder and attention-deficit/hyperactivity disorder. Conclusions: The results of this study demonstrate the importance of the impact of psychopathological comorbidity, particularly for the disorders associated with impulsivity and the control of impulses, in the therapeutic success of treatment in a therapeutic community.