It is widely assumed that after 1918 the British general staff ignored the experience it had gained from fighting a first-class European enemy and that it was not until the establishment of the Kirke committee in 1932 that it began to garner the lessons of the Great War and incorporate them into its doctrine. This article demonstrates that in fact British military doctrine underwent a continuous process of development in the 1920s. Far from turning its back on new military technologies, the general staff rejected the manpower-intensive doctrine that had sustained the army in 1914 in favour of one that placed modernity and machinery at the very core of its thinking. Between 1919 and 1931 the general staff did assimilate the lessons of the First World War into the army's written doctrine. But what it failed to do was to impose a common understanding of the meaning of that doctrine throughout the army.