Intravesical immunotherapy with live attenuated BCG remains the standard of care for patients with high-risk and intermediate-risk non-muscle-invasive bladder cancer (NMIBC). Most patients initially respond, but recurrence is frequent and progression to invasive cancer is a concern. No established and effective intravesical therapies are available for patients whose tumours recur after BCG, representing a clinically important unmet need. Development and discovery of treatment options for BCG-unresponsive NMIBC is a high priority in order to decrease the morbidity, burden of health-care expenditures, and mortality related to bladder cancer. This Review of treatment options after BCG failure focuses on principles of optimal management emerging therapies, thus enabling a synthesis of recommendations for management for such patients.