Partial cystectomy (PC) is a urological surgery in which only a portion of the bladder is resected for benign and/or oncological conditions. This surgery is indicated as an alternative to radical cystectomy (RC) in selected patients with the objective of achieving similar oncological efficacy with less morbidity. Selection criteria should include solitary tumors without concomitant carcinoma in situ (CIS) and amenable to resection with 1–2-cm margins in a normally functioning bladder. PC can be performed using different approaches (open, laparoscopic, or robot-assisted (RAPC)), with favorable oncological outcomes. The available evidence reports that 14% of patients present complications, which is a rate much lower compared to that of radical cystectomy. While there are no randomized trials, single institution series have demonstrated acceptable oncological outcomes when PC is indicated in selected patients. Therefore, offering PC to the appropriate patient, including to those who do not accept or are unfit for RC, represents an acceptable alternative. This chapter therefore explores our present knowledge of the proper indications and applications of this procedure.