Objective: To review trends in open partial nephrectomy (OPN) at our center, concentrating on patient selection, technique and perioperative complications., Methods: A comprehensive database was developed by chart review of consecutive patients undergoing OPN for renal masses at our center. Patient selection, technical modifications, perioperative morbidity, and histopathology were compared in patients undergoing OPN between 1992-1999, 2000-2003, and 2004-2008. Complications were divided into procedure-specific (PSCs) and nonspecific medical complications (NMCs). They were graded using the Common Terminology Criteria for Adverse Events (CTCAE), version 3.0., Results: One hundred and sixty-three OPNs were performed. Temporal trends identified include: an increase in the mean patient BMI (p = 0.04), an increase in the percentage of patients with central tumors (p < 0.001), decrease in cold ischemia time (p = 0.045), increasing use of a sequential renal vein clamp (p = 0.03), increasing utilization of tissue sealants (p < 0.001), reduced EBL (p = 0.05), reduced length of stay (p = 0.005), and a decline in PSCs from 16 to 7% (p = 0.002). The incidence of histologically benign tumors declined from 34 to 10% (p = 0.001). Thirty-three (20.2%) patients experienced perioperative complications: 70% were CTCAE grade 1 or 2 adverse events. BMI was the only factor that was found to be associated with the risk of complications on multivariate analysis [odds ratio 1.067, CI 95% (1.002-1.136); p = 0.031]., Conclusions: Increasingly, OPN is being utilized for a cohort of challenging patients who are overweight and have centrally located tumors. Despite this, the risk of PSCs is low. Patients who are overweight are at increased risk for perioperative NMCs.