Twenty-five patients with pure primary adenocarcinoma of the bladder were treated in a fifteen-year period. Practically all patients presented with some combination of gross hematuria, irritative lower urinary tract symptoms, or obstruction. Almost half the lesions were at the dome of the bladder. Most of the lesions were high grade and invasive. Transurethral resection is, at best, only diagnostic and palliative, and radiotherapy has been of little value. Radical cystectomy seems to produce five-year survival almost twice that of segmental resection. However, solitary lesions at the dome of the bladder, which usually represent neoplasia in a urachal remnant, seem to behave somewhat differently from lesions elsewhere in the bladder. Indeed, five-year survival of patients with lesions at the dome of the bladder who underwent segmental resection approximated that of those with similar lesions who underwent total cystectomy.