Private Lies: Infidelity and Betrayal of Intimacy is a non-fiction book by psychiatrist and family therapist Frank Pittman, M.D. Private Lies was first published in hardcover edition in 1989 by by the same publisher in a paperback edition in 1990. Dr. Pittman's book has been referred to as "widely quoted", by Psychology Today. It has been cited by 24 other books on marriage and family therapy counseling.