Anaerobic processes are widely used for the treatment of milk and dairy effluents. This technology has been subjected to significant development and real-scale application in the last few decades and offers highly favorable perspectives to accomplish a complete biodegradation of the components present in milk processing wastewaters such as sugars, proteins, and fats. Nowadays, anaerobic systems for the treatment of milk wastes can be operated successfully constituting an important contribution for the preservation of environmental quality.