There is a global interest in the application of thermochemical processing of sewage sludge resulting in numerous technologies entering the wastewater market. Gasification and pyrolysis are two of the technologies with the most experience utilizing 100% sewage sludge as a feedstock. In the current application in which anaerobic digestion is followed by drying and either pyrolysis or gasification, the energy and mass balance indicates that approximately 50% of the energy required for drying is available from the combustion of the fuel gases produced by the thermochemical process. This raises the question, is this the most efficient process flow arrangement? The subject of this presentation will be the energy and mass balance of the following different process flow scenarios: 1. dewatered, digested sludge, drying and pyrolysis, (baseline case), 2. THP, digested sludge, dewatering, drying and pyrolysis (advanced digestion scenario) 3. dewatered undigested sludge, drying and pyrolysis, 4. dewatered undigested sludge, THP, drying and pyrolysis, 5. digested sludge, THP, dewatering, drying and pyrolysis. Efficiency, measured as a percentage of thermal energy recovered for the drying process, suggests that the scenario producing the dryest cake may be the most efficient despite the difference in calorific value between digested and undigested sludge.