A review with 6 references on 3 fluid-bed processes that can be used in manufacturing controlled-released products. The process variables that should be optimized in the scale-up of fluid-bed processes are examined Such variables include the spray rate, the pressure of the atomization air, the temperature of the inlet air, the volume of the fluidization air, the batch size, and the type of equipment that is used. Because such parameters can easily alter the end performance of the controlled-release product, they should be carefully investigated during the scale-up operation.