Despite the availability of relatively inexpensive premium fuels, there are still many good reasons to consider one or more types of biomass as an industrial energy source, especially in a co-combustion mode with fossil fuels. In this report, biomass refers to wood, woodwaste, agricultural wastes, municipal refuse, sewage sludge, and cellosic-type industrial wastes. Burning biomass, fossil fuels together simplifies waste disposal, cuts fuel cost. There are few technical barriers to the application of co-combustion. All the major boiler/firing-system vendors have equipment offerings, most of them commonly referred to as multifuel boilers. Dutch ovens, flat and sloping pinhole grates, spreader stokers, traveling grates, mass-burn furnaces, and suspension and semi-suspension-fired boilers are all used in this application. Some of them are described. A list of power plants burning biomass in the USA is given in an appendix.