Of the many problems which face the physician who deals with renal failure, both acute and chronic, it is the purpose of this communication to touch upon only a few. The list is necessarily incomplete, and those which are to be discussed will be dealt with in a summary fashion, in the hope of highlighting them for future discussion rather than truly clarifying the issues involved.

For the purposes of this discussion let me somewhat arbitrarily classify renal failure into two groups. The first group comprises those patients whose renal disease is most strikingly manifested by renal losses, or "wasting." This is usually manifested by inability to conserve sodium (and bicarbonate), water, and occasionally potassium. The second group is characterized by inability to excrete, or "retention." In this case the retention consists of the products of metabolism and ingested food, i. e., potassium phosphates, sulfates, organic acids, "X-factors," and, most