Leslie Sokol, PhD, is a licensed psychologist, and an internationally recognized leader in the field of cognitive therapy with more than 35 years of experience in practice, teaching, and research. She was a past director of education and one of the principal instructors with the internationally acclaimed Beck Institute for Cognitive Behavioral Therapy in Philadelphia. She has taught cognitive therapy to professional and para professional groups, nationally and internationally, on such topics as: depression, anxiety, personality disorders, stress management, psychosis, substance abuse, and couples' problems.

Marci Fox, PhD, is a licensed psychologist, has been in private practice for over 25 years. She has worked closely with Dr. Sokol, Dr. Judith Beck, and Dr. Aaron T Beck at the Beck Institute for Cognitive Behavior Therapy in Philadelphia for almost the same amount of time. As an Adjunct Faculty Member at the Beck Institute, she trains individuals in cognitive therapy both nationally and internationally, and helps mental health professionals to improve their clinical skills and pinpoint specific areas of remediation.