In spite of decades of scientific research about radon, which has resulted in an immense corpus of literature and deep knowledge about all aspects of radon physics, its behaviour in the environment, its measurement and its dangers and benefits, many technical challenges remain. In course of increasingly strict regulation, new challenges emerged, mostly related to quality assured decision making in radon abatement policy and to application of advanced statistical methodology. In this paper, we give an overview about a number of topics of radon research, whose discussion and deeper investigation we find, at the one hand, important for the sake of implementing efficient radon abatement policy and interesting scientifically, on the other, as they elucidate the complexity of environmental systems up to their interaction with society in a paradigmatic manner.

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