This case study of long-term safety and effectiveness of copper IUDs was developed by the NDP/UNFPA/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP). The main sources of information for this report were: (1) interviews with HRP staff in Geneva responsible for the IUD programme; (2) interviews with non-HRP staff with long experience in IUD research and services in different geographical areas; (3) review of many HRP documents related to its IUD work; and (4) analysis of available information on use of IUDs in countries.