The Urinary Bladder: Structure, Functions and Clinical Aspects describes the detailed anatomy of the bladder, including its external and internal features, vasculature and lymphatic drainage, as well as its nerve supply. More than 90% of bladder cancers are urothelial carcinomas; the remaining are squamous cell carcinoma and adenocarcinoma. Approximately 75% of urothelial carcinomas are non-muscle invasive bladder cancers. Although promising biomarkers have been identified for urinary bladder cancer, none of them are used clinically due to limited validation and relatively low sensitivity and specificity. As such, the authors presents an overview of the recent developments in aberrant DNA methylation, one of the epigenetic mechanisms regulating gene expression. Additionally, new developments concerning the role of polymorphisms in glutathione gene family enzyme transferases are reviewed in the context of susceptibility to urinary bladder cancer. Immunotherapy, a novel promising targeted therapy for cancer treatment, is reviewed. Several approaches contributing to tumor recognition and cell death by the immune system have been adopted in oncology, such as immune checkpoint inhibitors, monoclonal antibodies, tumor vaccines, small molecules, and chimeric antigen receptor T-cells. Furthermore, various other diseases of the urinary bladder are enumerated through a pictorial review with a short note on each of the conditions.