The objective of this work is to assess how international law has been treated in the jurisprudence of the World Bank Administrative Tribunal (wbat). In so doing, the work will not deliver a thorough synopsis of the Tribunal’s jurisprudence, but rather a tour d’horizon of its most significant decisions related to the accomplishment of the above-named task. The notion of treatment indicates here the tools through which wbat judges have challenged international law. wbat judges have utilized both negative and positive references when considering international law; negative treatment has been utilized to differentiate wbat from other judicial bodies, while positive treatment has been employed to support the reasoning of the wbat. In this framework, the approach of the wbat will be examined in order to establish if it is prone to accepting international rules. The level of reception of external sources is considered to be an indicator of the wbat’s universalism or provincialism. Therefore, the work tries to demonstrate if the wbat is incorporated into the system of international courts and if the Tribunal might be alleged as an anti-fragmentation or a harmonizing body at the international level. Like the other international jurisdictions, the wbat is a tribunal with a restricted subject matter jurisdiction that does not have anti-fragmentation as a component of its mandate. Nevertheless, as an evolving court, the wbat should be fitted to the present fragmented normative scenario. Moreover, the wbat is a prominent tribunal; its jurisprudence might have an influence on the jurisprudence of numerous international jurisdictions. As such, it might theoretically diminish fragmentation at the international level.