Since the inception of the WTO, many have speculated on how the Dispute Settlement Mechanism's practices affect its legitimacy and suggested proposals to strengthen it in this respect. However, very few of these proposals are grounded in empirical evidence of what makes the Mechanism legitimate in the eyes of different constituents. Drawing on an original dataset of all statements made by WTO Members within meetings of the Dispute Settlement Body from 1995-2013 and a series of interviews, this paper provides a descriptive analysis of the aggregate and relative views on the DSM's exercise of authority over time and across actors. In addition, through an in-depth analysis of statements on focal reports, this paper sheds new light on the sources of an international court's legitimacy by identifying practices that contribute to reducing or enhancing the DSM's legitimacy in the eyes of its primary constituents - WTO Members.