Energy methods have had a degree of success in predicting noise energy transmission and distribution in a variety of structures, including automobile chassis structures. Classic noise transmission, in an analogy to sound transmission through walls, has been applied to large structures such as ships and aerospace structures. Statistical energy analysis (SEA) is a more recently developed procedure that has had considerable success, not only in structural analysis, but in purely acoustical and sound-structure interactions as well. Power (or energy) accountancy has also had application, particularly in manufacturing machinery. Since all of these deal with energy and its transport as principle variables, it would appear that there should be correspondences between them, at least under certain situations. Conversely, there should also be situations in which they provide different results, and it is perhaps even more important to understand those situations also. It is the purpose of this paper to discuss the ideas behind each of these procedures, and to provide the comparisons of concepts and applications.