So far the technology of anaerobic digestion has not been able to meet the predicted expectation to its potential. Many factors have been influencing this but a generally trend has been that the biogas plants constructed have had problems of both technical and financial art even they as a rule have been subsidised with close to 50%. Recently KRUGER has succeeded in construction of a new generation of standardised biogas plants for co-fermentation of both rural and urban wastes. The intention has been to put the technology back to its original enthusiasm by demonstrating viable solutions in both technical and financial terms. Furthermore, in 1997 a concept of energy neutral wastewater treatment has been demonstrated by means of co-digestion of sewage sludge and MSW which project was supported by the THERMIE programme of the EU. This concept has had an important impact to the chosen technical solutions at wastewater treatment plants and has contributed to a renewed interest in anaerobic digestion related to sewage plants.