This Supplement expands on the first edition of the ITU Handbook – Deployment of IMT-2000 Systems and represents much of the work that has occurred since the release of the Handbook to address among other topics, the subject of evolution and migration from the current mobile systems towards IMT-2000. ITU-R has developed this work in response to on-going liaisons and interaction with the ITU-D and ITU-T Sectors and sees this material as the natural extension of the information presented in the Handbook.