Embrapa Semi-Arid is honored to have been invited to the Second International Conference on Climate, Sustainability and Development in Semi-arid Regions (ICID+18), to participate and organize this book, presenting its main contributions in Research, Development and Innovation (RD&I) over the past 30 years for development of the Brazilian Semi-arid region. The aim of this book is to provide support to ICID+18, allowing participants to update their knowledge on relevant topics concerning semi-arid regions, especially regarding climate variability, the vulnerabilities and impacts posed by these changes and the public policies necessary to adapt production systems in semi-arid regions to these changes.