This article explores affinities between postindustrialism and modes of thinking characteristic of the Fabian Society, especially in the first half of the twentieth century. In the hands of Daniel Bell and others, the information society thesis postulates the coming of a postindustrial society marked by the centrality of information and knowledge. While caveats abound in Bell's version, the thesis has been generally optimistic in outlook, portraying postindustrial society as an advanced level of social development. Interestingly, the Fabian Society, a British-based organization highly influential in the twentieth-century project of social democracy, also emphasized information in its advocacy of social progress: ‘laying a foundation of fact’, according to one commentator, was a key ingredient of the Fabian approach. Texts by thinkers such as Sidney Webb and H.G. Wells suggest that ‘informationalism’, a commitment to information in an original sense of hard facts and figures, must indeed be construed as the essence of Fabianism, as that which distinguishes the Fabians from more metaphysical or emotional expressions of socialism. The article traces the link between information-powered politics and the largely successful practice of social engineering in Britain. However, social engineering can, and in the case of some Fabians did, degenerate into a technocratic and even totalitarian mindset. Critiques of Fabianism are therefore also acknowledged here, including those claiming that the Fabian preoccupation with data-gathering and filing, its ‘proceduralism’, actually constituted a major weakness. However, given its noble informational ideal, Fabianism can, the article concludes, illuminate contemporary information society problems. The Fabian tradition contains suggestive materials on such topical themes as fair access to information, the role of facts in progressive politics, and the prospects for an international institutional order.