Diversity in Britain is not what it used to be. Some thirty years of government policies, social service practices and public perceptions have been framed by a particular understanding of immigration and multicultural diversity. That is, Britain 's immigrant and ethnic minority population has conventionally been characterised by large, well-organized African-Caribbean and South Asian communities of citizens originally from Commonwealth countries or formerly colonial territories. Policy frameworks and public understanding - and, indeed, many areas of social science - have not caught up with recently emergent demographic and social patterns. Britain can now be characterised by 'super-diversity,' a notion intended to underline a level and kind of complexity surpassing anything the country has previously experienced. Such a condition is distinguished by a dynamic interplay of variables among an increased number of new, small and scattered, multiple-origin, transnationally connected, socio-economically differentiated and legally stratified immigrants who have arrived over the last decade. Outlined here, new patterns of super-diversity pose significant challenges for both policy and research.