The study explored changes in young adults’ mental health, attachment, and separation from parents during a seven-week wilderness therapy program. Utilizing a longitudinal one-group design, the study examined outcomes of 157 young adults in one wilderness therapy program. From pre to post treatment, participants reported significant improvement in mental health symptoms and interpersonal relationships, as well as increases in the belief that others can be depended upon. Participants reported less resentment and anger towards mothers from pre to post treatment, but an increase in their needs for approval from fathers. The study details a link between young adults’ attachment, independence from parents, and improvement in mental health, suggesting that treatment which targets these links may provide more effective intervention.