Dropsy, or edema, is usually defined as the accumulation of serous fluid in the intercellular spaces of the subcutaneous or deeper tissues and in the serous cavities. The source of this fluid is the blood, from which it has escaped by passage through the walls of the blood vessels. Edema is always but one manifestation— although sometimes the most dramatic and important— of some abnormality or disease process, and its removal by medical means should logically begin with treatment of the causative process. Specific measures for its removal are necessary only if its location or extent render it harmful or uncomfortable to the patient and should ordinarily be employed only after correction or treatment of the underlying abnormality. There are many conditions with which edema may be associated, but only a few of these will be considered in this review, which is concerned primarily with the practical aspects of medical