While fear of immigration is regularly expressed in terms of numbers, it is the perceived impacts of immigration – economic, social and cultural – which fuel that concern. Yet the factors which facilitate or impede integration processes in Europe remain significantly under researched and policy intervention consequently lacks a strong evidence base. The very concept of ‘integration’ and contrasting, normative national models of policy intervention remain highly contested, distracting attention in Migration Studies and policy debate from the actual processes in which individuals, groups and institutions are engaged. In this seminar I shall draw on my recent work to present a heuristic model of integration processes capable of empirical and policy application; and will argue that understanding the multi directional processes in which migrants (regardless of legal status) are with others engaged, across separate but related domains of integration, and the macro and micro factors which impact on them, should be one core part of developing the new conceptual and analytical tools capable of understanding migration in the 21st century.