The effect on the nephrotic syndrome of activation of the adrenal cortex by ACTH was investigated in 8 cases. All patients were given a diet containing approx. 700 mg. of salt. ACTH was given in divided doses; the daily total and the length of the course varied with the wt. of the patient. Na, K, Cl, P, creatinine, total N, and protein were detd. on 24-hr. collections of urine, and blood chemistries were performed weekly. Eosinophil counts were taken daily. It was concluded that an appropiate stimulus to the adrenal cortex by the admn. of adrenocorticotropin can produce marked modifications in the nephrotic syndrome[long dash]reduction in serum cholesterol and urine protein, increase in serum proteins and profound diuresis. With one exception the diuresis occurred after discontinuence of ACTH, and the improvement in N balance and serum values continued for several weeks.