Medical physics in the Nordic countries: the past, the present and the future.

Medical physics as a separate profession developed from both theoretical and experimental physics. In the current understanding of the scope of the medical physics domain, the field is usually considered to be born with Röntgen’s discovery of x-rays in 1895. However, physical laws and relationships are also underpinning other biomedical applications and techniques that have a longer history, such as hyperthermia. The majority of medical physicists today still work in the fields of radiotherapy, medical imaging and nuclear medicine, in which use of highenergy ionising radiation is the common component. Röntgen’s x-rays, Marie and Pierre Curie’s gamma rays and the other radiation modalities that have followed represent the essence of the medical physics profession’s existence. As mentioned by Steve Webb in his combined historic and futuristic outlook paper published in this issue, most of the early achievements within the field of medical physics were performed by physicists and engineers that did not consider themselves as being medical physicists [1]. This was also the case for the Nordic scientists who earned a place in the medical physics history books for their scientific achievements in the early part of last century. Gustaf Ising, Rolf Sievert and Lars Leksell from Sweden as well as Rolf Widerøe from Norway are among those mentioned in Webb’s overview in this issue. Readers are referred to Webb’s paper for further details of the achievement of these early Nordic scientists from which our profession has developed. The first Nordic medical physics meeting was held in 1962 (in Örebro, Sweden) while the Nordic Association of Clinical Physics (NACP) was formally founded in 1965, only a few years later than e.g. the American Association of Physicists in Medicine (AAPM) that has celebrated its 50 anniversary in 2008. This reflects the strong dedication and professionalism of the scientists involved in these early days of Nordic medical physics. Already in 1965 1966, NACP had formed eight different working groups, within the topics dosimetry, radiation protection, treatment planning data, education, betatron dosimetry, simulation techniques, isotope techniques and electronic data management/treatment planning. At this time, NACP had 81 regular members (41 from Sweden, 21 from Denmark, 11 from Finland and 8 from Norway) in addition to its first honorary member, Rolf Sievert. The NACP meeting in 1966 (in Hangö, Finland) attracted more than 100 participants, the majority from outside of the Nordic countries; proceedings from this meeting were also published. It is also interesting to note that NACP was formed before several of the Nordic national societies that it now acts as an umbrella organisation for, i.e., the Norwegian Society for Medical Physics was formed in 1976, the Danish Society for Medical Physics in 1981 while the Icelandic Society for Biomedical Engineering and Medical Physics was formed in 2000. In Finland, the hospital physicist branch of the Finnish Society for Mathematicians and Physicists was founded in the