This article explores the adult learning theories that might affect the way that adult learners perceive learning and reach understanding of clinical expertise. Although educators in clinical and simulation settings are becoming much more aware of the theories that affect adult learning, too often their knowledge might not reach past the great work of Malcolm Knowles and his theory of androgogy. Other theories are presented in ways that help adult educators of adults to understand how the conditions that are favorable for adult learning may be replicated to help learners reach a level of understanding, meet clinical and organizational objectives, and willingly seek out lifelong learning opportunities.