The puzzle of the political signifi cance of expert knowledge has many dimensions, and in this chapter I plan to explore a simple Oakeshottian question in relation to it. To what extent is the present role of expert knowledge similar to that envisioned by the “planners” of the 1940s who were the inspiration for Oakeshott’s essay, “Rationalism in Politics” ([1947-48] 1962)? This role, as Oakeshott and many of its enthusiasts portrayed it, was to replace politics as hitherto practiced with something diff erent. Rationalism thus depended on a theory of the “politics” it sought to supplant, though it rarely attempted to articulate this theory. In the context of the time, there was no need. In the 1930s, economic depression and the inability of party politicians in the British parliament to agree on measures to deal with the economic situation provided endless negative examples of “politics” standing in the way of action, and a sharp contrast with the state activism of Hitler, Mussolini, and Stalin. In the postwar period, the planners had their chance, and the modem British welfare state was born. Much of what this state did applied ideas of Fabian Socialism, which had presented itself as objective, rational, and expert. But as an administrative fact, the welfare state had no need of the ideology of planning, and the discussion faded. The question I wish to address here is this: expertise forms a much larger part of governance than it did in the time of the “rationalism” of the planning movement; does this mean that rationalism has arrived by stealth, that is to say in practice, without appealing to the overt ideology of rationalistic planning? This is a question of the place of expertise in our politics, and thus a political question.