Intravesical therapy has been used in the management of superficial transitional cell carcinoma (TCC) of the urinary bladder (i.e., Ta, Tl, and carcinoma in situ) with specific objectives which include treating existing/residual tumor, preventing recurrence of tumor, preventing disease progression, and prolonging survival. The initial clinical stage and grade remain the main determinant factors in survival irrespective of the treatment. Presently, bacillus Calmette-Guerin (BCG) immunotherapy remains the most effective treatment and prophylaxis for TCC (Ta, Tl, CIS) and has positive outcomes on tumor recurrence rate, disease progression, and prolongation of survival. Prostatic urethral mucosal involvement with bladder cancer can be effectively treated with BCG intravesical immunotherapy-it has demonstrated a reduction in tumor recurrence rates, but has had no positive impact on disease progression or prolongation of survival. Interferons, keyhole-limpet hemocyanin (KLH), bropirimine, and PHOTOFRIN-photodynamic therapy (PDT) are under investigation in the management of TCC and early results are encouraging. This comprehensive review highlights recent developments in intravesical therapy of bladder cancer and summarizes the mechanisms of action of BCG, and the important role of intravesical BCG immunotherapy and other immunotherapeutic agents in the therapy and prophylaxis of superficial TCC of the urinary bladder.