Incineration of ion-exchange resins in a fluidized bed was studied on the pilot plant scale. Granular resins were incinerated mostly in the dry form, while powdered resins were incinerated in an ethanol-water mixture. Incineration converts the organic resin into inert oxide material, which can be immobilized for instance with cement. The weight of the ash was 1 to 20% and the volume 2 to 30% of the original resins, which contained 15 to 25% moisture. When immobilized with cement the volume of the ash-concrete is 4 to 22% of the concrete of equal compressive strength acquired by direct solidification. The absorption of cesium and cobalt in various bed materials was studied by means of inactive tracer materials. Biotite and chamotte absorbed significantly, but this absorption does not drastically help on the off-gas side. The sintering of the bed materials in the presence of sodium was studied. Corundum, chamotte, and biotite have a safety limit of 5% sodium of the bed’s weight at 850°C.