This chapter identifies an evolving trend in the ICJ’s engagement with science, which has started with the marginalization of scientific evidence, continued with making superficial evidentiary assessments, but ultimately demonstrated an increasing willingness to engage with science. As to framing techniques, mandating the parties’ negotiations in science-intensive questions, the prevalence of finding procedural breaches as well as decoupling the notion of ’risk’ from substantive, scientific criteria will be discussed. In terms of fact-finding, the chapter addresses evolving procedures for taking expert evidence, and applicable standards of proof. The causal analysis evidences the Court’s struggle with establishing the requisite proof in cases of uncertain causation. As to the standard and extent of review, the study examines the reasonableness test, and defends the majority's solution in the Whaling in the Antarctic case based on insights from Science and Technology Studies.