One Health, the concept of combined veterinary and human health, has now expanded beyond emerging infectious diseases and zoonoses to incorporate a wider suite of health issues. Retaining its interdisciplinary focus which combines theory with practice, this new edition illustrates the contribution of One Health collaborations to real-world issues such as sanitation, economics, food security and vaccination programs. It includes more non-infectious disease issues and climate change discussion alongside revised case studies and expanded methodology chapters to draw out implications for practice. Promoting an action-based, solutions-oriented approach, highlights the lessons learned for both human and animal health professionals and students.