"The CLANDESTINO research project was designed to support policy makers in developing and implementing appropriate policies regarding undocumented migration. The project aims were to (a) provide an inventory of data and estimates on undocumented migration (stocks and flows) in selected EU countries, (b) analyse these data comparatively, (c) discuss the ethical and methodological issues involved in the collection of data, the elaboration of estimates and their use, (d) propose a new method for evaluating and classifying data/estimates on undocumented migration in the EU." (Quoted from paper)