Heidi L. Heard, PhD, has published numerous articles and chapters related to borderline personality disorder and DBT and is coauthor (with Michaela A. Swales) of Dialectical Behaviour Therapy: Distinctive Features. She collaborated with Marsha Linehan on the initial outcome trials for standard DBT and the adaptation for substance abuse and dependence, particularly focusing on the cost-effectiveness of DBT. Now retired, Dr. Heard was the founder of British Isles DBT Training and was a senior trainer for Behavioral Tech, which provides advanced training in DBT internationally. She provided consultation in the United States and Europe to DBT teams working in adult and adolescent outpatient programs and in adult secure inpatient programs, and to individual clinicians in adult outpatient, secure hospital, and prison settings.

Michaela A. Swales, PhD, is Consultant Clinical Psychologist and Professor in Clinical Psychology on the North Wales Clinical Psychology Programme, Bangor University. She trained in DBT with Marsha Linehan and for 20 years ran a clinical program for suicidal young people in an inpatient service. Dr. Swales is Director of the British Isles DBT Training Team, an international affiliate of the Linehan Institute. She has trained more than a thousand professionals in DBT, seeding over 400 programs globally. She coauthored Dialectical Behaviour Therapy: Distinctive Features (with Heidi L. Heard) and is editor of the Oxford Handbook of Dialectical Behaviour Therapy. Her primary research interest is the effective implementation of evidence-based psychological therapies in routine clinical practice. Dr. Swales was a member of the Working Group on Classification of Personality Disorders reporting to the World Health Organization's International Advisory Group for the Revision of the ICD-10 Mental and Behavioural Disorders.