This book is motivated by a question: when should international courts intervene in domestic affairs? To answer this question thoroughly, the book is broken down into a series of separate inquiries: when is intervention legitimate? When can international courts identify good legal solutions? When will intervention initiate useful processes? When will it lead to good outcomes? These inquiries are answered based on reviewing judgments of international courts, strategic analysis, and empirical findings. The book outlines under which conditions intervention by international courts is recommended and evaluates the implications that international courts have on society.