INTRODUCTION

It is clear that there is no comprehensive universal legal framework governing the mobility of human beings. Nonetheless, it is generally agreed that there are numerous, albeit somewhat scattered, elements of a legal and normative framework, derived from binding global and regional instruments and accompanied by informal and non-binding understandings among States.

The exact nature and status of this assemblage is subject to debate, but the research literature leaves readers in no doubt that they are in the presence of work in progress. The body of dispersed, disparate, rather unevenly joined items has been characterised variously as an emergent regime or ‘substance without architecture’. Lillich’s early observation that the topic of the rights of aliens in international law was like a ‘giant unassembled jigsaw’ may appropriately be applied today to the more comprehensive framework now thought needed, or at least desirable, to ensure effective governance of human mobility in all of its manifestations. Construction sites abound. Some have a bilateral regulatory focus, as in the case of the management of labour migration flows; some have a rights-based orientation and dwell on the definition and protection of those rights; still others address mobility from the point of view of the necessity to balance facilitation of movement with entry control. Some boast robust and finished structures, such as the International Convention on the Protection of the Rights of All Migrant Workers and Members of their Families (1990); others are best conceptualised simply as passageways to major adjoining policy areas, such as trade.