A better understanding of clinicians' attitudes toward evidence-based treatments (EBT) will presumably enhance the transfer of EBTs for substance-abusing adolescents from research to clinical application. The reliability and validity of two measures of therapist attitudes toward EBT were examined: the Evidence-Based Practice Attitude Scale (Aarons, 2004), and Attitudes Toward Psychotherapy Treatment Manuals Scale (Addis & Krasnow, 2000). Participants included 543 public sector, master's-level mental health and substance abuse therapists who treat adolescents. Factor analyses generally corroborated factor structures of the instruments found previously. Beliefs that EBTs negatively affect treatment process were associated with relatively low openness to new treatments and with beliefs that EBTs do not produce positive outcomes. (Contains 5 notes and 4 tables.)