It is now well known that disturbances in the electrolyte patterns of the intracellular fluid, as well as in those of the extracellular fluid, may play a significant role in many disease states. Darrow and associates (1) (2)(3)(4)(5)(6)(7)(8), by study of the distribution of radioactive sodium (9), and by tissue analyses of skeletal muscle (10) and of erythrocytes (9, 11). These observations have suggested that both low potassium intake and hyperadrenocortical function are implicated in the etiology of this disturbance. In addition to these two etiological factors a third has been postulated, namely, impaired renal conservation of the potassium ion (12).The purpose of the present study is to examine, in a group of patients with metabolic alkalosis and hypokaliemia, 1) the direction and magnitude of intracellular electrolyte abnormalities as revealed by the balance technic, 2) the relation of these abnormalities to the extracellular hypochloremia and elevation of bicarbonate, and 3) the relative etio-