The quality of the relationship between the sterile processing department (SPD) and the operating room (OR) is an important determinant of OR safety and performance. In this article, the concept of "friction" refers to the SPD behaviors and attributes that can negatively affect OR performance. Panels of SPD professionals initially were asked to identify and operationally define different ways in which behaviors of a hospital,s SPD could compromise OR performance. A national convenience sample of OR nurses (N = 291) rated 14 frictions in terms of their agreement or disagreement that each had a negative effect on OR performance in their hospital. Overall, more than 50% of the entire sample agreed that 2 frictions, "SPD does not communicate effectively with the OR" (55%) and "SPD inventories are insufficient for surgical volume" (52%), had negative effect on OR performance. However, a latent class analysis revealed 3 distinct classes of nurses who varied with respect to their level of agreement that SPD-OR frictions negatively affected OR performance. The observed heterogeneity in how different groups of nurses viewed different frictions suggests that effective efforts aimed at reducing performance-limiting frictions should be customized so that resources can be used where they are most needed. Copyright © 2014 Lippincott Williams & Wilkins.