Abstract
This chapter explores the complex and controversial path of MDMA-assisted therapy (MDMA-AT) for treating post-traumatic stress disorder (PTSD) and other behavioral disorders. It covers MDMA's history from research to recreation to medicine, the pivotal trials, and the challenges faced by researchers. Despite recent setbacks for the clinical application of MDMA, the chapter argues that it holds potential for transforming psychiatry and discusses the uncertain future amidst ongoing debates over ethics, methodology, and political influence.