The course provides theoretical and experimental knowledge of the detection of ionizing radiation and a good knowledge of measurement technology. The course covers measurement of small currents and charges, pulse height analysis, pulse statistics, recombination and dead time corrections. Gas, scintillation and semiconductor detectors are treated as well as neutron detectors and photographic film, TLD etc. Furthermore, gamma spectroscopy and experimental determination of activity including low activity measurements are covered. The course includes a mandatory laboratory part.