Abstract Thinking in terms of order is believed to be a feature of several liberal economic schools, most famously the ordoliberal school. This article demonstrates that the work of Jan Tinbergen provides a good example of “thinking in orders” on the left. His analysis of the national and international economic system is conducted in terms of order, and he believed that economic stability was primarily the result of the institutional order of an economy. This article shows that these ideas were shaped in discussions over the Plan of Labor (comparable to the New Deal) in the Netherlands as well as during his period in Geneva at the League of Nations. Crucial in Tinbergen's work on order is the optimal set of institutions, a so-called optimal order, that specifies the right level of centralization and decentralization in economic decision making. This focus on order is an important move away from the equilibrium-focused work on econometric studies of the business cycle theories of the 1930s. By showing the importance of the discussions in Geneva for Tinbergen's work, the article also problematizes Slobodian's recent argument that the Geneva school was neoliberal in nature. Instead, we demonstrate that it is better understood as internationalist and bipartisan.