Evidence for activity against the lignin fraction of straw was produced for a range of actinomycete strains. Decolorization of the polymeric dye Poly R and oxidation of veratryl alcohol, indicators of ligninolytic activity in white rot fungi, and utilization of fractionated Kraft lignin and low-molecular-weight methoxylated aromatic compounds were the criteria used. The relationships between these activities and the solubilization of native lignin are discussed.