We examine why international actors—including states, firms, and activists—seek different types of legalized arrangements to solve political and substantive problems. We show how particular forms of legalization provide superior institutional solutions in different circumstances. We begin by examining the baseline advantages of “hard” legalization (that is, precise, legally binding obligations with appropriate third-party delegation). We emphasize, however, that actors often prefer softer forms of legalization (that is, various combinations of reduced precision, less stringent obligation, and weaker delegation). Soft legalization has a number of significant advantages, including that it is easier to achieve, provides strategies for dealing with uncertainty, infringes less on sovereignty, and facilitates compromise among differentiated actors.
Although our approach is largely interest-based, we explicitly incorporate the normative elements that are central in law and in recent international relations theorizing. We also consider the important role of nonstate actors who, along with states, are central participants in contemporary international legalization. We illustrate the advantages of various forms of international legal arrangements with examples drawn from articles in this special issue and elsewhere.