This chapter discusses how various theories of learning and forms of pedagogy shape the technologies used to instantiate them, and how the evolution of computers and telecommunications is widening the range of instructional designs available. Three alternative schools of thought on how people learn have strongly influenced the design of instructional technologies: Behaviorism, Cognitivism, and Constructivism. Behaviorist instructional technologies are limited both in what they can teach and in the types of engagement they offer to learners, but are useful for tasks involving learning facts and simple procedural skills. Scholars disagree on how broad a range of knowledge and skills Cognitivist instructional technologies can teach, but they are effective for well-defined content and skills that have a few correct ways of accomplishing tasks. Constructivist approaches can teach a very broad spectrum of knowledge and skills, however, the efficiency of Constructivist technologies for material that these other two schools of thought can teach is questionable. Emerging technologies such as multi-user virtual environments and augmented realities enable new types of pedagogical strategies based on situated learning.