Dialectical Behavior Therapy (DBT) is an evidence-based practice for borderline personality disorder (BPD) and suicidal behavior that has been replicated with a variety of populations. Patients' practice of behavioral skills taught in the group skills training component of DBT may be partly responsible for the positive treatment outcomes according to the skills deficit model of BPD that underlies DBT. This study was designed to examine the type and frequency of skills practiced by DBT patients. Participants were 49 women, who met criteria for BPD and current and chronic suicidal behavior, receiving 1 year of standard DBT as part of a clinical trial. Skills were recorded on the daily diary cards completed by participants each week and reviewed by their individual therapists. Results indicated that the majority of participants reported practicing skills most days throughout treatment. Crisis survival and mindfulness skills were practiced most frequently in our sample. Hierarchical linear modeling demonstrated that skills practice increased as a function of time in therapy. Directions for future research are discussed. (Contains 1 figure and 2 tables.)