Micros 2017 17th International Symposium on Microdosimetry An Interdisciplinary Meeting on Ionising Radiation Quality, Molecular Mechanisms, Cellular Effects, and Their Consequences for Low Level Risk Assessment and Radiation Therapy *** The Symposium is intended to provide a forum for scientists from different disciplines to exchange and discuss recent data and findings on relevant basic physical and biological mechanisms of radiation action and their consequences for risk assessment and radiation therapy, including proton and ion therapy. The 17th Symposium will be a celebration of the 50th Anniversary of the Symposium, and continues the eminent tradition by promoting and encouraging interdisciplinary interactions between advances in physical and chemical techniques and knowledge, combined with the latest rapid advances in molecular and cellular biology and genetics. Moreover, room will be dedicated to the recent technical developments in radiation detection and novel irradiation techniques as well as to discuss the current status of topical non-linear phenomena and to review the progress made in modelling radiation action and the multi-step process of radiation induced cancer and neuro-radiobiology with application to epidemiological data, in particular for the better quantification of low-dose and low-dose-rate risks. In order to maximize interdisciplinary communication and discussion the Symposium will be structured as Invited, Oral and Posters presentations. Refresher courses by invited experts are also foreseen. To encourage the attendance of young scientists as well as researchers from less-favoured-Countries, specific awards are foreseen.