Energy development is an integral part of enhanced economic development. The fact that expanded provision and use of energy services is strongly associated with economic development leaves open how important energy is as a causal factor in economic development, however; and energy development competes with other opportunities for scarce capital and opportunities for policy and institutional reform. In this paper we first give a brief conceptual discussion that seeks to identify the channels through which increased availability of energy services might be a key to stimulating economic development along different stages of the development process. We then examine some empirical work to see what evidence it might provide regarding possible channels of influence. The evidence underscores the importance of energy development in concert with other forms of development. More work is needed to better understand the magnitude of energy's importance for economic development.