Leonard Sax, M.D., Ph.D., is a board-certified family physician, psychologist, and author of Why Gender Matters, Boys Adrift, and The Collapse of Parenting. As the founder and executive director of the National Association for Single Sex Public Education (NASSPE), Sax has spoken on child development in over a dozen countries and has appeared across major broadcast radio and television, including programs on CBS, CNN, Fox, CBC, BBC, and PBS. Sax lives with his family in in Chester County, Pennsylvania.