This ITU-R Supplement expands on the first edition of the ITU Handbook on 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 current mobile systems towards IMT-2000. This Supplement will serve as a practical tool to assist countries in their endeavours to further develop their mobile communication networks and enhance the quality of services offered.