 This randomized, placebo-controlled pilot study of MDMA-assisted psychotherapy in 18 people with anxiety stemming from a life-threatening illness examines the safety and efficacy of this treatment. This study will allow comparison between the impact of placebo and an active dose of MDMA-assisted psychotherapy on anxiety, depression, sleep quality, global functioning, attitudes toward death, posttraumatic growth, mindfulness, self-compassion, and overall quality of life. 