Defining moments are situations that ask us to step forward in irreversible courses of action that shape our personal or professional identities. These moments of truth happen quickly and reveal something new about ourselves that had been hidden or only partially known. In a process known as "edgework," experiential educators and therapists invite participants outside their comfort zone into an area of the unknown and the unpredictable. The edge of the comfort zone is a place of imbalance where learning, insights, and self-knowledge occur and where defining moments may happen. Psychological conditions that facilitate learning and create a ripe environment for the emergence of defining moments include hope, effort, constructive level of anxiety, trust, perceived risk, and sense of unpredictability. The skills of a facilitator can shape and support defining moments. The facilitator must attend to the emotional needs of students and clients by establishing learning environments that are physically and emotionally safe. Simultaneously, the facilitator should establish rapport and honor participants' right to choose their level of involvement. Pitfalls for the facilitator to avoid are listed, and facilitator actions before, during, and after the learning experience are outlined. (SV)