The diabetic neurogenic paralytic bladder is characterized by marked residual urine, secondary infection, pyelonephritis, sepsis, and azotemia. Initial manifestations were studied in diabetic patients with and without neuropathy and in nondiabetic controls, all without symptoms referable to the urinary tract. The nondiabetic controls and the diabetics without neuropathy were urologically normal. Eighty-three percent of the diabetic patients with neuropathy had objective evidence of neurogenic bladder involvement; however, there was no residual urine, infection, pyelonephritis, sepsis or azotemia. The disparity between early and late bladder involvement is determined by the factor of residual urine, which is the measure of advancing bladder neuropathy leading to decompensation. Progressive decompensation of the asymptomatic diabetic bladder may be a cause of the increased frequency of renal infection in diabetic patients.