Beginning with the decommissioning of nuclear power plants the release criteria for radioactive materials has gained importance significantly. After decommissioning and dismantling, most of the residues need not be treated as radioactive waste, since they contain only small amounts of radioactivity. The Karlsruhe Research Center already dismantled two research reactors completely (the Karlstein Super Heated Steam Reactor and the Niederaichbach Nuclear Power Plant), while several additional decommissioning projects are currently in progress. About 70 % of the total waste mass within each project can be released from the area of atomic regulations and licenses. At the Niederaichbach and Karlstein sites the release procedures and the release criteria were determined in the decommissioning license, where issues such as controlling and release values were fixed. Additionally, each step of the release process has to be coordinated with the regulator. Today the general release criteria are contained in the atomic act. Depending on the nature of the material to be released (e.g. building structures or metallic waste), and depending on the further use of the material, such as unrestricted reuse or waste disposal, release values for each nuclide are established. To prepare the release of materials, a release plan including the release measurement results is sent to the regulator, who has to officially approve the concept.