With the technical innovations of smaller, flexible ureteroscopes, color-filtered imaging, and endoscopic laser technology, organ-preserving treatment for upper urinary tract transitional cell carcinoma has become feasible. While in the past, radical nephroureterectomy was the sole gold standard approach for the treatment of upper urinary tract tumors, the endoscopic approach is no longer restricted to only patients with the imperative indication of kidney preservation. Initial clinical results have demonstrated oncologic efficacy of endoscopic management or segmental ureteral resection. However, careful preoperative risk-assessment and close endoscopic follow-up are mandatory.