Abstract: Dialectical Behavior Therapy for Adolescents (DBT-A) is an acceptance and change-based treatment protocol that includes parent participation, and has been shown to be effective with emotionally dysregulated, suicidal, and self-injurious adolescents (Mehlum et al., 2014, 2016) who often show high rates of treatment utilization and subsequent dropout (Groves, Backer, van den Bosch, & Miller, 2012). Despite its demonstrated effectiveness and despite parents’ active role in treatment, there is limited treatment acceptability data for DBT-A, and even less investigation into the parent perspective. Pretreatment expectancies and preferences are two common factors associated with treatment acceptability that have been shown to influence treatment participation, adherence, and outcomes that can inform methods for enhancing evidence-based treatments, yet remain underinvestigated (Nock & Kazdin, 2001; Wymbs et al., 2015). The primary goal of the current study was to assess parent pretreatment expectancies and preferences prior to entering an outpatient DBT-A program with their adolescents. Twenty-three parents completed two self-report assessment measures just prior to starting treatment: The Parent Expectancies for Treatment Scale (PETS; Nock & Kazdin, 2001), and the Parent Preferences for Treatment form developed for this study to assess preferences for eight alternative treatment delivery formats. Results showed that parents had moderately high overall expectancies for DBT-A ( M = 97.78, SD = 9.03). Subscale analyses indicated high parent expectancies for its credibility (Credibility, M = 52.09, SD = 5.44), moderately high expectancies for child improvement (Child Improvement, M = 23.43, SD = 3.49), and moderate expectancies for parent involvement (Parent Involvement, M = 22.17, SD = 2.98). Highest rated expectancies were related to the credibility of DBT-A as a valuable, worthwhile treatment and the large role of parent involvement in treatment. The four most preferred alternative format options were to add weekly skills training for individual families, weekly individual parenting skills sessions, weekly parent-only support groups, and weekly parent therapy sessions. The two least preferred format options involved partially or fully separating parent and teens in multifamily skills group. This study provides preliminary support for the use of assessing parents’ pretreatment expectancies and preferences for DBT-A as an initial step toward understanding the treatment attitudes and desires of parents with teens referred to DBT-A. Clinical implications for the utility of these findings in clinical practice and future research are discussed.