You may be wondering why we chose a photo of astronauts working in space on the Space Station for the cover. We actually chose it for several reasons. Obviously, it is very exciting; in fact, space represents the most exciting frontier for the entire world! In addition, much of the station itself consists of all kinds of circuits! One of the most signiﬁcant circuits within the station is its power distribution system. It is a complete and self-contained, modern power generation and distribution system. That is why NASA (especially NASA-Glenn) continues to be at the forefront of both theoretical as well as applied power system research and development. The technology that has gone into the development of space exploration continues to ﬁnd itself impacting terrestrial technology in many important ways. For some of you, this will be an important career path.