This journal article describes a qualitative study of 29 young adults (ages 18 to 25) living in permanent supportive housing (PSH) about their feelings of ontological security. The authors define ontological security as a feeling of well-being derived from a sense of order from one’s social and material environment. The study found ontological security (e.g., constancy, routine, control) positively affected the participants’ mental health and well-being, which helped with positive identity construction. An increase in ontological security also related to residents’ social environment and their ability to strengthen social relationships, which supported improved mental health and sense of self. Most young adults in this study regarded living in PSH as an opportunity to start their lives over and imagine their futures in a normative developmental trajectory.