Interest in introducing radiation technology into the polymer and plastics industry is growing. This publication summarizes a number of studies conducted in the framework of an IAEA coordinated research project (CRP) on controlling degradation effects on polymers by radiation processing technologies. It reviews a variety of applications and details the most important results and achievements of the participating centres and laboratories during the course of the CRP. The publication is intended to be of use to scientists implementing the technology and to managers of radiation processing facilities.