Standards are receiving increasing attention, especially at the transnational level where standardization aims at coherence and social ordering beyond the nation-state. However, many attempts to bring about uniformity via formalized standards fail. To understand better how such rules successfully span national and organizational boundaries over time, we compare two cases of standardization in international business. Both Windows desktop software and International Accounting Standards demonstrate the need for a process perspective to understand and explain social ordering through standards. Long-lasting standardization processes require conceptualizing how different sequences of transnational standardization relate to each other. We find that at the core of such recursive cycles is the interplay of input and output legitimacy.