Excavated plans of roundhouses may compound multiple episodes of activity, design, construction, occupation, repair, and closure, reflecting successive stages of the building’s biography. What does not survive archaeologically can only be inferred from context or comparative evidence. The great diversity in structural components suggests a greater diversity of superstructure than was implied by the classic Wessex roundhouses. Among the stone-built houses of the Atlantic north and west there likewise appears to have been a range of regional and chronological variants in the radial roundhouse series, and probably within the monumental Atlantic roundhouses too. Important though recognition of structural variants may be, morphological classification should not be allowed to override the social use of space for which the buildings were designed. Atlantic roundhouses reveal an important division between central space and peripheral space, and a similar division may be inferred for lowland timber roundhouses, where the surviving evidence is more ephemeral. Some larger houses were evidently byre-houses or barn-houses, some with upper or mezzanine floor levels. Some of these may have functioned as ‘great houses’ serving community needs beyond those of the resident extended family. The increased scale of development-led excavations of recent years has resulted in an increased database that enables evaluation of individual sites in a wider landscape environment than was previously possible. Circumstances of recovery and recording in commercially driven excavations, however, are not always compatible with research objectives, and improvements in standards of environmental investigation are sometimes offset by shortcomings in the publication of basic structural or stratigraphic detail.