Biogas has unique properties for improving the biodegradability of biomass solids during anaerobic digestion (AD). This report presents batch test results of the first investigation into utilizing biogas plasticization to "condition" organic polymers during active digestion of waste activated sludge (WAS). Preliminary design calculations based on polymer diffusion rate limitation are presented. Analysis fo the 20 degrees C batch test data determined the first order (k(1)) COD conversion coefficent to be 0.167 day(-1) with a maximum COD utilization rate of 11.25gL(-1) day(-1). Comparision of these batch test results to typical conventional AD performance parameters showed orders of magnitude improvement. These results show that biogas plasticization during active AD could greatly improve renewable energy yields from biomass waste materials such as MSW RDF, STP sludges, food waste, animal manure, green wastes, and agricultural crop residuals.