Anaerobic digestion is a core technology for sustainable waste(water) management and renewable energy recovery from waste sources. This book introduces and brings readers up to date with anaerobic digestion and its applications. It refreshes readers on the fundamentals of anaerobic digestion processes for normal and stressed scenarios, introduces techniques for stable system operation and predication, and explains the innovation in technology applications for waste valorization. By providing scientific and engineering fundamentals, the book equips professionals with the knowledge of knowing why and how to solve the problems in the application of anaerobic digestion.