Disease or treatment oriented registries form an integral part of modern medicine. They complement industry driven, corporate group sponsored and institutional research and are, together with prospective randomised trials cornerstones of modern evidence based medicine. Focus has been on rapid collection, analysis and dissemination of information on rare procedures with stress on patient outcome. In complex expensive procedures, such as hematopoietic stem cell transplants (HSCT), novel structures are required to catch outcome at team or national level. The annual activity survey of the European Group for Blood and Marrow Transplants EBMT forms such an instrument. Since 1990, EBMT has been collecting, on an annual basis, numbers of HSCT from the preceding year according to indication, donor type and stem cell source. The survey covers all European countries. In 1990, 143 teams reported 4,234 HSCT; in the year 2000, 619 teams reported 19,136 HSCT (33% allogeneic, 67% autologous). This information, which covers over 90% of all HSCT performed in Europe and is based on 132,963 HSCT (33% allogeneic, 67% autologous), gives a clear overview of current status and ongoing trends. It shows the general increase in HSCT from 1990 to 2000 with few exceptions, such as autologous HSCT for breast cancer and allogeneic HSCT for chronic myeloid leukemia. It illustrates the shift in technology from bone marrow as stem cell source in 1990 (100%) to peripheral blood in 2000 (96% of autologous, 53% of allogeneic HSCT). Supplemented by population data and economic factors (Gross national Product, Health Care Expenditures, Health Care systems) of the individual countries it allows comparison of transplant rates (Number of transplants per 10 million inhabitants), team densities (Number of transplant teams per 10 million inhabitants) and trends between countries. It permits quantification of the impact of economics and health care systems and provides a basis for quality control and allows assessment of the main factors influencing team decisions: evidence, disease prevalence, economics and expectations. As such, it is an essential tool for patient counselling and health care planning.