While this review of the subject of nephritis is intended primarily to summarize the most recent developments in that field, it is impossible to do so without going back into the literature of the past twenty years to trace the outlines of the growth of the present concepts and to give orientation to the discussion. I wish to state frankly at the outset that I have made no attempt to give a complete bibliography, even of the literature of the past year. Keeping in mind the desirability of clarity and the necessary limitation of space, I have sought to digest the great mass of literature and to quote key articles from which a more detailed bibliography can be obtained. The modern trend of thought about Bright's disease began to crystallize twenty years ago with the publication of "Die Brightsche Nierenkrankheit," by Volhard and Fahr,1 who introduced an anatomic and