This chapter is the Introduction to the Sage Handbook of E-Learning Research (2007), edited by Richard Andrews and Caroline Haythornthwaite. The introduction, written by the editors, is a substantial work that addresses definitional issues about e-learning research; it begins with an exploration of the ???e??? and ???learning??? components in e-learning, and continues with theoretical and methodological issues, and a model and discussion of co-evolutionary processes of technology and learning. The publication of the Handbook marks a significant point in studies in e-learning. Although there has been considerable development in teaching and learning, as well as in learning design, there is as yet no coherent view of what constitutes research...