Psychiatric illnesses - including major depressive disorder, anxiety disorder, posttraumatic stress disorder, and substance use disorders - are widely prevalent and represent a significant health care burden worldwide. For many affected people, existing treatments provide incomplete relief from disruptive and disabling symptoms. On March 29-30, 2022, this workshop will explore the therapeutic use of psychedelics and entactogens for these disorders. Speakers will discuss the current state of knowledge regarding mechanisms of action and clinical efficacy; considerations for research, clinical trial design, and regulatory approval; bioethical and legal issues; and opportunities to move the field forward.