Book excerpt: FAO in the 21st Century: Ensuring Food Security in a Changing World details the current knowledge of complex and interrelated challenges that are compounding efforts to achieve global food security. It discusses likely implications for the food and agriculture sector and for hunger and poverty reduction efforts, including FAO's role in assisting members in the coming years. This book is for everyone interested in better understanding the dynamics of the current global issues and changing patterns in agriculture and natural resources.