The place of Charles Booth's London poverty survey within an empirical tradition of sociology has been much discussed in recent years. The pivotal position which Booth had in this tradition was highlighted by Philip Abrams especially. Booth's achievement, it has been claimed, was to illuminate the structural underpinnings of poverty rather than just its extent. In doing so he not only challenged the assumptions of political economy but brought new life to the tradition of house-to-house surveys and case-studies as practised by those involved in the statistical movement of the nineteenth century in Britain. Booth sought answers to narrowly denned social problems, seeking to generate new and superior data capable of bearing the questions. His was the habit of ‘ad hoc compartmentalised research’, from which one main line of development was the government enquiries of the Webb era and beyond. Another line of descent can be traced in the social survey movement centred in the United States, and through this Booth's influence spread to the Chicago school of urban sociologists. Despite this wideranging influence those who followed Booth's lead studied his own descriptions of his findings and methods, and rarely, if ever, looked behind the published volumes to the varied materials generated by the large-scale research project he masterminded. These materials represent a rich and varied source of data which have so far been relatively little used by historians, and then mainly in a minor illustrative way.