The most important single advantage of the IUD as a contraceptive method is that the couple need make only the decision to have it inserted. Thereafter, so long as the IUD remains in place, no further contraceptive action is required. Other advantages of the IUD include a high level of protection, easy insertion and removal, a minimum of medical supervision, low production costs, and complete stability under all climatic conditions.The IUD has been endorsed as a method of contraception by national and international health authorities19 and has been well accepted by the populations of many countries. In the United States, IUD's are included among the methods offered in most family planning clinics, including tax-supported services, and by a growing number of gynecologists in private practice.Although the advantages of the IUD as a method of contraception weigh heavily at any level of economic and social development, they are particularly applicable in those situations where the population is not accustomed to contraceptive practice, is economically disadvantaged, has limited educational opportunities, and where medical services are in short supply. The IUD has thus become the mainstay of the population control program in many countries.Through March, 1966, about 600,000 insertions had been made in India; 350,000 in Korea; 160,000 in Taiwan; and 100,000 in Pakistan.13 Other areas with rapidly expanding IUD programs include Ceylon, Chile, Hong Kong, Thailand, Tunisia, Turkey, and Singapore. And the list of countries continues to grow.It can be estimated that, up to the time of this writing, about 1.5 million women all over the world have had an IUD inserted. Even if 2 out of 5 of these women expel the device, or have it removed, or become pregnant, almost one million will still remain protected against an unwanted pregnancy in the years to come. The hope may be justified that a real breakthrough in the population problem is now within man's teach.