Until the discovery of ionizing radiation, medicine knew no effective remedy for cancer other than surgery. A new era in cancer treatment was started by great discoveries at the end of the nineteenth century: the discovery of x-rays by Wilhelm K. Rijntgen in 1895, and the discovery of radium by Marie Sklodowska-Curie (who was born and received her basic education in Poland) and her husband Pierre Curie in 1899. X-rays were first used in cancer treatment just 1 year after the discovery. The relatively low energy of radiation that could be generated at that time limited the application of x-rays chiefly to the treatment of skin cancer. Already before the outbreak of World War I, curietherapy was recognized as a successful cancer treatment modality. This new treatment modality brought about the high interest of medical circles worldwide, as well as in Poland. From 1906 on, the Committee for Studies and Control Cancer, organized by Dr. J. Jaworski in Warsaw, and renamed in 1921 to become the Polish Cancer Control Committee, was actively operating in Poland. Its main aims were to support cancer research and to promote the exchange of ideas, which led to the creation of a periodical Nowolwory, which has existed for over 70 years. The Polish Cancer Control Committee was also in charge of organizing congresses and assisted in the promotion and development of cancer treatment centers. Although these centers were usually rather small, ephemeral, and organized in a variety of ways (by universities, local authorities, or private persons), they managed to gather about 3 g of radium during the period between the wars. At the same time, research carried out by the Laboratory Curie in Paris developed dynamically. The staff included many foreigners, among them Polish physicists (Irena Manteuffel, Cezary Pawlowski, and Jerzy Starkiewicz) and chemists (Alicja Dorabialska and Ignacy Zlotowski). Maria Sklodowska-Curie’s greatest dream was, in her own words, to establish a radium institute in Poland. She saw it as an exemplary center running comprehensive research and treatment programs. At her initiative and under her honorary leadership, the Association of Radium Institute was established in 192 1. In December 1923, on the 25th anniversary of the discovery of radium, the Polish Cancer Control Committee made an appeal to the people of Poland to raise funds. The National Donation Committee was established with the President of Poland, Stanislaw Wojciechowski, serving as its chairman. Donations and government subsidies soon enabled the construction of the Institute in Warsaw on Wawelska Street. On June 7, 1925, the first cornerstones were laid. The Institute included four buildings: the hospital, the roentgenotherapy pavilion, a research building housing the physics department and laboratories, and the so-called Hot Pavilion with radioactive sources. Dr. Franciszek Lukaszczyk trained in the Laboratory Pasteur with Professor Regaud and became the Director of the Radium Institute. Since that time, our link with the French radiotherapeutic centers has always been close and friendly. Dr. Cezary Pawlowski went to the Laboratory Curie in 1927, and under the supervision of Maria Sklodowska-Curie, acquainted himself for 4 years with the future scientific projects, organization, and the equipment of the physics department in Warsaw. Maria SklodowskaCurie came to Poland in May, 1932, to preside over the opening ceremony of the clinical part of the Radium Institute, and to transfer the first gram of radium, which she received as a donation from the Polish women’s organization in the United States. The research buildings of the Radium Institute were finished in 1934. In 1932, Franciszek Lukaszczyk, the first Director of the Institute, outlined the program of the development of oncology in Poland. This program consisted of three phases: (a) organization of a modern oncological institute for clinical services and research, (b) elaboration on a scientific basis of modern methods of cancer treatment, and (c) organization of an oncological network in Poland.