Anaerobic fermentation of cattle dung alone or with paddy straw, mango leaves or foliage of Parthenium hysterophorus in uninsulated, small capacity, batch-type out-door digesters of cylindrical and cuboid shapes gave encouraging results at initial total solids (TS) concentrations of 16-19%. The gas yield on a unit digester volume basis varied from 202.2 to 499.3 litres/day/m3 for 7 weeks retention period and 196.2-407.7 litres/day/m3 for 10 weeks retention period as compared to 204-372 litres/day/m3 in the case of semicontinuous type conventional digesters that used water-diluted cattle dung at 8-9% TS concentration at 7 weeks retention time. Gas yield per kg of TS fed was, however, significantly lower than from a semicontinuous type, conventional, digester. The digestion process was, in general, severely affected at TS concentrations in excess of 19%. The gas yield was also affected by season of the year and pretreatment of the agro-residues used. The substrate at the end of the trials was loaded straight on to a trolley and transported to fields for use as manure. Seeds of pathenium passed through the plant were found non-viable after retention for 93 days.