Professional development in simulation methodologies is essential for implementation of quality, consistent, simulation-based experiences. Evidence demonstrates that participation in comprehensive training positively impacts learner outcomes. There are many benefits to professional development, however, challenges exist requiring thoughtful planning, administrative buy-in, and fiscal support. While there are no established guidelines, the literature provides an ongoing consensus related to overall concepts and strategies for training in simulation. We describe a continuum of growth for simulationists, ranging from novice/advanced beginner, competent/proficient, to expert. As a novice, one must conduct a self-assessment of current strengths and create a development plan to advance simulation skills and knowledge. A simulationist should use evidenced-base guidelines, mentorship, and feedback to inform simulation practices. They should be knowledgeable of the standards of best practice, modalities, simulation design, learning theories, and professional integrity. Simulationists must seek ongoing advancement through certification, scholarship, and lifelong learning. This chapter describes the continuum of education and methodologies for the development of simulationists.