Simulation-based learning (SBL) has been the focus of higher-education literature, especially in teacher education and training. Led by a professional facilitator, the SBL process requires learners to step out of their comfort zone. This multiple case-study examines the roles of SBL facilitators to better understand the conditions for creating an optimal learning setting. Triangulation was accomplished using three data-collection methods: 218 facilitators' written reflections were collected; a focus group was held with eight SBL facilitators; and interviews were held with 21 SBL participants. Data analysis revealed six themes describing the facilitator's multiple roles: removing barriers to promote participants' openness to learn; reducing stress; counterbalancing harsh criticism; gauging the intensity of the scenario; pacing the learning process; linking the learned lesson to practice. Conceptualizing the SBL facilitator's role as the combination of these opposing poles suggests that the facilitator's goal is to create a 'stretch zone' that promotes effective learning.