In this ground-breaking study, the issues and prospects of a multilateral response to the challenge of movements of people is explored. It presents, within a single, cohesive framework, the views, perceptions, and critical analyses of a group of eminent specialists drawn from different disciplines. It introduces the concept of an internationally harmonized migration regime, based on the principle of regulated openness--commonalty of policy objectives, harmonized normative principles, and co-ordinated institutional arrangements.