Exploring the dynamics of migratory change first of all requires examining the how and why of migration. This chapter first discusses the main explanatory frameworks that have shaped migration research over the past century, from economic disparities and complementarities, over social networks and migration information, to household and individual characteristics. It subsequently builds upon recent attempts to integrate these different approaches in a three-level explanatory framework that allows us to separate the influence of structural historical change on the evolution of migration behaviour from the part played by individual variations. A third section finally explores the implications of the proposed framework for the dynamics of migratory change to arrive at the central heuristic devices that structure this book: selectivity, resilience and the speeds of change.

Explanatory Frameworks in Migration Research

One apparent problem of overall generalizations on the causes of migration is that those that stand the test turn out to be as trivial as they are true: that is, that people move with an eye to better opportunities than they had or expected to have where they were. These propositions in turn have the greatest difficulty in explaining why only some of those in comparable conditions move, and why those who do move go to specific places and not to others where overall prospects might be even better. To explain why people move in the numbers and directions and for the lengths of time they do, migration research generally employs one or more of three main explanatory frameworks: economic disparities, social networks and household and individual characteristics. This book will adopt a theoretical perspective which builds on recent attempts to incorporate various migration research traditions in one theoretical framework by integrating macro (structural social and economic conditions), meso (social networks and information channels) and micro (household and individual characteristics) levels of explanation. To clarify the direction and nature of the different causal mechanisms eventually integrated in the three-level approach, I will discuss each of the three levels and their associated explanatory frameworks separately, before discussing their mutual interactions.