Background: No study exists on preparatory time—from patient’s entrance into the operating room to skin incision—and its role in hand surgery operating room inefficiency. The purpose of this study was to investigate the length and variability of preparatory time and assess the relationship between several variables and preparatory time. Methods: Consecutive upper extremity cases performed for a period of 1 month by hand surgeons were reviewed at 3 surgical sites. Preparatory time was compared across locations. Cases at one location were further analyzed to assess the relationship between preparatory time and several variables. Both traditional statistical methods and Shewhart control charts, a quality control tool, were used for data analysis. Results: A total of 288 cases were performed. The mean preparatory times at the 3 sites were 25.1, 25.7, and 20.7 minutes, respectivley. Aggregated preparatory time averaged 24.4 (range 7-61) minutes, was 75% the length of the surgical time, and accounted for 34% of total operating room time. Control charts confirmed substantial variability at all locations, signifying a poorly defined process. At a single site, where 189 cases were performed by 14 different surgeons, there was no difference in preparatory time by case type, American Society of Anesthesiologists status, or case start time. Preparatory time varied by surgeon and anesthesia type. Conclusions: Preparatory time was found to be a source of inefficiency, independent of the surgical site. Control charts reinforced large variations, signifying a poorly designed process. Surgeon seemingly plays an important, albeit likely indirect, role. Efforts to improve operating room workflow should include preparatory time.