Monitoring of cesium-137 and strontium-90 in consumption milk is a sub-programme of a national monitoring program regarding environmental radiation in Sweden. The sub-programme has been ongoing since 1955. In the event of increased deposition of radionuclides, e.g. after a nuclear accident, transfer to cow milk is a quick process. The concentration in milk is therefore a good indicator of any changes of the levels of radionuclides in the area. Monitoring is performed at 5 dairies: Umeå, Sundsvall, Kallhäll, Jönköping and Malmö, where milk is sampled 4 times per year.