It is important to begin this concluding chapter by re-emphasizing the issues which this study does and does not address. Research based on a sample of individual longitudinal migration histories is not a substitute for aggregate studies of net and gross migration flows between administrative units derived from census and vital registration data. Such studies have been completed for those years when relevant data are available in Britain: they depict the broad outlines of regional demographic change and emphasize the net effects of inter-regional migration flows (Friedlander and Roshier, 1966; Lawton, 1968a; 1983). However, there are many issues which such studies cannot tackle, and it is these lacunae that data on life-time residential histories can begin to fill. In particular, data collected from family historians are ideally suited to investigation of the ways in which migration and mobility changed over the life-course; the links between life-time migration experiences and migrant characteristics; examination of the reasons why people moved; investigation of the relative significance of short distance and circulatory moves (which are not revealed in aggregate census-based studies); assessment of the significance of mobility between different places; and examination of the relative importance of movement within and between different parts of the country. Previous chapters have focused on such issues and, in doing so, have complemented the information available from most existing studies of migration.