Despite almost 30 years of research and practice, the field of outsourcing still suffers from ambiguous definitions and lacks guidelines for strategic implementation. . This article answers two main questions, relevant to researchers and practitioners: 1.What are the main findings so far in outsourcing literature? 2.What do we need to learn? In doing that we referred to a recognized framework for a comprehensive survey of the existing literature and the principal mainstream theories. We propose a research agenda to investigate outsourcing decisions based on an integrated and longitudinal approach. Finally, we draw some implications for managerial education and practitioners.