Though UN peacekeeping has changed dramatically since its inception, peacekeepers are still ostensibly committed to the “holy trinity” of consent, impartiality, and minimum use of force. Impartiality has come under special pressure, as peacekeepers are increasingly expected not only to observe the situation, but to take forceful action against “spoiler” groups that threaten the peace or human rights. This essay draws on official statements, outside analysis, and a number of interviews with peacekeepers conducted by the author and his research assistant, to demonstrate that a wide variety of understandings of “impartiality” currently exist, potentially undermining peacekeeping operations. The author attempts to systematize these variations according to how they understand the standard of impartiality, the process for making impartial decisions, and the scope of operations that fall under the concept. Ultimately, the author argues for an understanding of impartiality that is practically focused on achieving peace and includes structured consultations with all parties as a conceptual necessity, not just a helpful technique.