This IDS Bulletin is an oddity: a publication by an institute specialising in developing countries, which consists almost entirely of papers about developed countries. There is a justification, however. It lies in the rapid growth in writing about a new concept, 'social exclusion'. Despite some pioneering work by the International Institute of Labour Studies on social exclusion in the South2, most writing on social exclusion has been in and about the North, originally in France, but now more widely. The new writing represents new thinking on a new problem, namely the rapid growth of poverty in rich countries. Poverty has been driven rapidly up the policy and research agendas of the European welfare states, of the USA, and also of Eastern Europe's transitional countries. Increasingly, it is discussed in the vocabulary of social exclusion.