Sheri L. Turrell (Author) Sheri L. Turrell, PhD, is a clinical psychologist living with her family in Toronto, ON, Canada. She is passionate about her clinical work with adolescents, helping them to move towards a life that matters. Sheri is the primary investigator, working in collaboration with Mary Bell, for studies of group-based acceptance and commitment therapy (ACT) and a mobile app for adolescents. Sheri runs a full-time private practice, and enjoys being a consultant for graduate students and mental health service providers who are interested in learning ACT. Christopher McCurry (Author) Christopher McCurry, PhD, is a clinical child psychologist in private practice specializing in the treatment of childhood anxiety. He is a clinical assistant professor in the departments of psychology and psychiatry at the University of Washington in Seattle, WA. Mary Bell (Author) Mary Bell, MSW, RSW, is a social worker working in private practice and clinical roles in Singapore and Toronto, ON, Canada. She specializes in helping youths and their parents through the adolescent transition. Her clinical affiliations have included The Hospital for Sick Children (SickKids), The Centre for Addiction and Mental Health (CAMH), and Trillium Health Partners. She has found her 'true north' in sharing acceptance and commitment therapy (ACT) with both clients and other practitioners.