A method for recovering fission-product cesium from aged basic fission-product waste with an aluminosilicate ion exchanger (Decalso) was developed and demonstrated. Cesium is selectively adsorbed on Decalso from Hanford Purex Supernatant 103A, a basic 9 NaNO3 solution, and concentrated by a factor of about 8.5. The Decalso column is transported from HAPO to ORNL in shielded containers formerly used for shipping solutions, and the cesium is eluted with ammonium salts for purification and source fabrication. In the period April 1961 to August 1964, 2MCi of 137Cs was recovered from Hanford wastes and transported to ORNL by this procedure.