The Estimation of Illegal Migration in Europe

Abstract

The author examines available methods and techniques for the estimation of the phenomenon of illegal migration in Europe, illustrated by examples of applied research in the field from a number of European countries and supplemented by his own research. Following an introduction to the debate and a concise discussion of terms and definitions used, a variety of methodologies for estimating the size of hidden populations and clandestine entries is presented and illustrated by concrete examples of research studies into the subject. The methods and examples are then subjected to a critical discussion and review. Dividing the methodologies into those used for estimating stocks of illegal migrants (illegal foreign residence and illegal foreign employment) and those used for estimating illegal migration flows (illegal entries), it emerges that the analytical toolkit for producing estimates on stocks is by far greater and more promising than the techniques available for estimating flows. Finally, the author argues that rational policy making in the field of illegal migration needs to rely more on serious estimation techniques, rather than simple guesswork, and that the methods for doing so are available and tested.