Science is identifying new biological processes that determine a person’s sex. How will these findings affect the transgender and transsexual community? This program explores the latest research into gender development and the medical, cultural, and legal issues at the heart of the “brain sex” school of thought. Showing how human genome research has shifted scientific focus away from chromosomes, the video examines the role of brain receptors and the discovery of the SRY protein, which establishes maleness. Interviews featuring people with intersex and transsexual experiences shed light on how gender identity emerges, and how it figured into one man’s legal battle for the right to marry.