MUCH IS KNOWN about the manifestations and natural course of myeloma, but there are features that have not been adequately elaborated. Information on progressive changes in various measurements during the course of illness would have particular value, as one might use serial observation of these measures more effectively in evaluating potential therapeutic agents. The establishment of objective criteria has permitted a more precise evaluation of new drugs in the treatment of acuteleukemia. The present study was initiated to provide information which would be similarly helpful in the evaluation of therapy in multiple myeloma. This report is concerned with diagnosis, indications for treatment, and most distressing manifestations of multiple myeloma, and particularly with patient survival. A subsequent publication will explore more fully the potential utility of various other measures as yardsticks of therapy in multiple myeloma.