This book examines where and how the two different obligations imposed by the WTO law and the POPs Convention meet and create a situation of conflict. Chapter I deal with the rationale behind POPs Convention. For a better understanding, the Convention is explained by means of five main purposes. These purposes are incorporated in the Convention as a whole. Chapter II examines the WTO provisions, Article I:1, Article IX:1 and Article XX of the GATT 1994 as well as Articles 27 and 28 of the TRIPS Agreement. The compatibility between the two international obligations is analyzed in Chapter III. The probable solution is one balancing the obligation between WTO law and POPs Convention and it is discussed in Chapter IV.