It was not until 1980 that cancer registration was started in Korea; official registration began with the financial supportof World Health Organization on July 1st of that year. Forty-five training and two non-training hospitals throughout thecountry initiated voluntary registration of patients in whom neoplasia had been found. All completed data sheets, containing15 items of patient information, were to be sent from each hospital to the Korean Central Cancer Registry Center (KCCR)at the National Medical Center (1). A few years later, the Ministry of Health and Welfare compelled all the university andtraining hospitals to join the program.The KCCR has continued without interruption and has published an annual report. The number of member hospitals andregistered cancer cases has been increasing steadily year by year. In 1998, around 89,000 cases from 124 hospitals wereregistered throughout the country (2). Although the KCCR is a national cancer control program and covers almost all thelarge training hospitals in Korea, it cannot provide incidence data. It is, however, the only registry of its kind in the world,being neither population nor hospital based.In 1983, a PBCR was launched in a small county, Kangwha, by Yonsei University Medical College. Kangwha County isa small island area connected by a bridge to the mainland, and is 50 Km from Seoul. It has around 80,000 inhabitants. Alldata were collected by active methods, and incidence statistics for 1986-1992 appeared in Vol. VII of the Cancer Incidencein Five Continents . However, the population covered is too small to be representative of the whole of Korea.In 1990, the initial study for a PBCR in Seoul was carried out by several researchers including this author. It was supportedby a civilian foundation, the Korean Foundation for Cancer Research. The study had two objectives:1) to test thefeasibility of operating a population based cancer registry in the Seoul area, with dual sources of case registration, i.e.,from the KCCR, but incorporating cases diagnosed in small hospitals, and 2) to provide the cancer incidence for all sites inthe Seoul area with completeness and validity assessment. In 1993 the major findings were reported, and it was suggestedthat the methods of data collection used in the study could be used as a model for a future population based cancer registryin other areas of Korea (3). The Seoul cancer registry (SCR) started in 1991 and has operated continuously since then (4).The program and methodology used by the SCR was later extended to other large cities: Busan in 1995, Daegu and Kwangjuin 1996, Incheon in 1997, and Daejeon in 1998 (Fig1). In each area a study of patterns of utilization of existing medicalfacilities by cancer patients was first carried out, and after this the registry was launched. As of 2000, six population basedcancer registries are running in Korea. The Kangwha area, the earliest registry area, merged with Incheon.