Scientific Diasporas Scientific Diasporas A New Approach to the Brain Drain ...The migration of scientists and engineers between countries with different levels of development has long been a critical issue and an unsolved problem. Today, with the global knowledge-based economy increasingly relying on science and technology (S&T) skills and generating their international flows more than ever before, the issue has become even more crucial. However, the terms in which this concern is being addressed are changing, possibly giving way to new solutions. The rise of intellectual, especially S&T, diaspora networks during the last decade all over the developing world indicates such a new trend. Though the experiences differ from one country to the other, they all share the goal of systematically using their expatriate experts, scientists and engineers for development at home. Some lessons and policy implications may already be extracted from these recent attempts. They should pave the way for an efficient use of the S&T diasporas. These are indeed strong potential resources for effective and mutually beneficial co-operation between developing and highly industrialised countries.