This paper reviews, in some detail, the general theory of MHD induction generators. Several different approaches to the analysis of constant-velocity generators are summarized and compared, and a new mathematical model for a variable-velocity generator is presented, including digital computer solutions for the theoretical performance. The velocity distribution and boundary layer losses are considered separately, and the problem of end effect is discussed qualitatively. Recent experimental results for both separately excited and self-excited MHD induction generators are summarized, and the future of MHD induction generators is discussed briefly.