The development of domestic architecture in Oxford during the late medieval and sub-medieval periods, that is to say, from the fourteenth century to the eighteenth century, will be discussed in the following paper, with a double purpose in view. The first purpose is to report on a certain amount of research work done on old Oxford houses during the last ten years, in which a good many people have taken part. The second purpose is to sketch a plan of campaign, or to indicate certain lines of investigation and classification, which might, I think, mutatis mutandis, be applied to other towns. We badly need a systematic survey of the old houses in various towns in England, with plans, elevations, sections, and analyses. This is particularly needed at a time when so much is in danger of destruction, and it is a work which one hopes the Society of Antiquaries may encourage.