Three cases of signet-ring cell adenocarcinoma of the bladder are presented: a primary vesical adenocarcinoma, a metastatic one, and a signet-ring cell adenocarcinoma of the urachus. A review of the literature found 69 additional reports of primary signet-ring cell adenocarcinoma, 20 of urachal signet-ring carcinoma, and 4 of the metastatic variety. The pathogenesis, clinical, and histologic findings, prognosis, and management are discussed.