This chapter discusses the interrelationship of augmented and virtual reality and Universal Design for Learning (UDL). It provides the results of a structured literature review, proving that there is still very little research on UDL in AR/VR trainings. Furthermore, an exemplary AR/VR learning scenario for craftsmen is presented, developed as part of the German research project ARSuL (Augmented Reality Based Support for Learning in the HVAC industry). The chapter reflects selected design elements behind first AR and VR prototypes of the project through the lens of UDL. Weaknesses are identified and opportunities for improvement derived from UDL principles, guidelines, and checklists.