The relation between vancomycin clearance and renal function was studied in 22 patients with various degrees of renal functional impairment and in four normal volunteers. Clearance of vancomycin and creatinine were highly correlated (r = 0.92) among 17 persons not on dialysis. In five dialysis patients vancomycin clearance averaged 0.086 mL/min . kg of body weight (+/- SEM = 0.025). These relations enabled us to construct a nomogram for vancomycin dosage adjustment (based on a mean steady-state serum vancomycin concentration of 15 micrograms/mL) in patients with various degrees of renal functional impairment.