The law of the World Trade Organization (WTO) both explicitly and implicitly requires that a determination of causation be made at a number of points. In several of the WTO covered agreements, an important part of making a determination about causation involves separating those factors that are causative from those that are immaterial to the outcome in question (this process of separation is known as a ‘non-attribution analysis’). This thesis argues that there are six parts of the law of the WTO that require, either explicitly or implicitly, that a causation and non-attribution analysis be undertaken. These are: (1) Safeguard Measures (Articles 2.1 and 4.2(a) and (b) of the Agreement on Safeguards ); (2) Anti-Dumping measures (Articles 3.1 and 3.5 of the Anti-Dumping Agreement ); (3) Countervailing Duties (Article 15.5 of the Subsidies and Countervailing Measures Agreement (SCM Agreement)); (4) Serious prejudice (Articles 5(c) and 6.3 of the SCM Agreement); (5) the relationship between a measure and its policy objective (Article XX of the General Agreement on Tariffs and Trade and Article XIV of the General Agreement on Trade in Services ); and (6) the relationship between a responding Member’s failure to comply with a DSB ruling and the complainant Member’s level of nullification and impairment (Articles 22.6 of the Understanding on Rules and Procedures Governing the Settlement of Disputes and 4.10 of the SCM Agreement). This thesis will first examine the current approach in the jurisprudence to analysing causation and non-attribution in these parts of the law of the WTO. To that end, it will suggest that there is a trend in the current jurisprudence to attempt to make an a priori inference about the effects of a cause from the nature of the cause itself. This thesis will suggest that this approach reflects a misconception of causation, and it will propose an alternative, three-part methodology for interrogating causation based on the use of econometric analysis, which has been developed from guidance given by the Appellate Body in US—Wheat Gluten.