Amid the proliferation of international judicial and quasi-judicial bodies, worries about the possible fragmentation of international law are increasing. Such fears, however, may be misplaced. A close examination of the jurisprudence of nine international judicial bodies, looking specifically for instances of explicit reference to one another's decisions, shows the practice to be widespread, of variable frequency and covering both procedural and substantive issues. Taken in conjunction with other scholarship about the similar treatment of important doctrines across all (or most) bodies, this study suggests that unity, not fragmentation, may emerge from the proliferation of international courts and tribunals.