Distance education, which began as correspondence courses in the nineteenth century and grew into educational television during the twentieth century, evolved into learning on the Web by the mid-1990s. Accompanying the rise in online learning has been a similar rise in organizations and publications dedicated to serving the needs of online educators and exploring issues related to this evolving instructional modality. Online learning has become entrenched in the educational scene. It is only expected to grow during the coming years as more students demand it and as more faculty accept it. Despite the growth of online instruction and the unique needs it addresses, it has not achieved universal acceptance, and there are those who hold distance education to higher standards than traditional instruction. Any institution or teacher seeking to venture into the online realm needs to be fully aware of these emerging challenges. The prospect of greater scrutiny, however, may prompt the development of online offerings that exceed traditional quality and effectiveness expectations. This chapter provides a brief history of online learning and a discussion of the empirical evidence for its acceptance and effectiveness.