While energy is essential for development, standard fossil fuels are often in short supply in countries where it is needed most. However, alternative fuel resources abound in the form of agricultural and municipal waste or 'biomass'. This report reviews the state of the art of biomass combustion and gassification systems, their advantages and disadvantages. It also encourages investment in use of these technologies to enable developing countries to better exploit their biomass resources and help close the gap between their energy needs and their energy supply.