The fluidized bed combustion of a number of alternative fuels of practical interest has been analyzed by a combination of experimental and modeling techniques. Solid fuels of widely different origin (biomass, agricultural, civil and industrial wastes) have been considered in this work. A lab-scale experimental campaign was carried out to evaluate the comminution (fragmentation, attrition) behavior of the fuels. Experimental results have been used as input parameters in a stationary one-dimensional model of an atmospheric bubbling fluidized bed combustor, suitable for high-volatile solid fuels. Model results are presented for a typical set of operating variables and discussed with respect to location of combustion of fixed carbon and volatile matter and heat release profile in the combustor. Differences between the combustion behavior of the various fuels considered are highlighted.