The Introduction provides an overview of the complex interplay between law and diplomacy. It argues that the reach of international humanitarian justice has expanded significantly over the past decades, and although the principles and dynamics underlying judicial and diplomatic processes have remained essentially unchanged, judicial and political institutions are clearly and fundamentally different. When there are judicial and political institutions involved in the same situation, there is significant potential for confusion and contradictions. This book does not address in detail the peace versus justice debate, which has been extensively explored. Instead, the five case studies— Accountability (Bosnia), Legal Terminology (Rwanda), Compliance (Kosovo), Timing & Signaling (Darfur), and Alignment between Processes (Libya)—provide examinations of those moments in international crises where parallel diplomatic and judicial processes meet and occasionally collide. The purpose is to permit diplomats and jurists alike to derive insights and lessons that can better inform future decision-making processes.