The aim of this study was to evaluate outcomes of robotic partial nephrectomy (RAPN) procedures. At two centers, 42 patients underwent RAPN. Radius, Exo/Endophytic, Nearness, Anterior/Posterior, Location (R.E.N.A.L.) nephrometry and PADUA scores of patients were calculated by computed tomography (CT) or magnetic resonance imaging (MRI). Intra-and perioperative (0-30 days) complications were evaluated using modified Clavien classification. A four-arm da Vinci-S robotic surgical system was used and outcomes were evaluated retrospectively. Mean age of the patients was 52.3 +/- 6.5 years. Mean tumor size was 3.1 +/- 1.0 (1.4-6.6) cm. R.E.N.A.L. nephrometry and PADUA scores were 6.0 +/- 1.5 and 7.5 +/- 0.9, respectively. Mean surgical time was 127.7 +/- 18.7 minutes and estimated blood loss was 100 +/- 18.1 cc. Mean warm ischemia time was 16.0 +/- 8.9 (0-30) minutes. Intraoperative complications did not develop in any patient. Median hospital stay was 3.0 (2-6) days. Except for 17 patients, hilar clamping was performed in 25 patients. Histopathology results included 34 renal cell carcinoma (22 clear cell, 7 chromophobe cell, 4 papillary cell, and 1 clear papillary cell). Oncocytoma (n = 4), adenoma (n = 1), fibroadipose tissue (n = 1), papillary epithelial hyperplasia (n = 1), and chronic pyelonephritis (n = 1) were present. Surgical margins were negative in all patients. During a median follow-up period of 15.5 +/- 10.9 (3-46) months, neither local recurrence nor distant metastasis was detected. In conclusion, RAPN is a safe, minimally invasive surgical approach, with excellent surgical and oncological outcomes in T1 kidney tumors. Zero ischemia off-clamp RAPN is also safe in selected masses with the advantage of avoiding complete renal ischemia. Copyright (C) 2015, Kaohsiung Medical University. Published by Elsevier Taiwan LLC.