Measurements have been made to determine the scattered radiation to be expected from typical multicurie Csl37 installations. For the cesium pellet sources investigated the scattered intensity ranged from 12 to 21 per cent of the total incident radiation intensity. The source capsule is responsible for scattered intensity of about 8 per cent with the source material contributing the bulk of the balance. The source material scatter, for a source diameter of 3.6 cm, is about 5 per cent per centimeter for source thicknesses of up to about 1.5 cm.