[en] A large number of data must be collected, documented and updated at the different stages of waste, from the source to its preliminary treatment, conditioning, transport, interim storage, and delivery to a repository, in order to allow the origin technical quality with respect to safety, and disposal of the waste to be kept under control. What data to collect, document, and update in connection with waste flow control is specified in the so-called Waste Control Directive issued by the German Federal Ministry of the Environment (BMU) in 1989, and in the Radiation Protection Ordinance of 2001. Supplementary requirements to be met in transport are laid down in the applicable regulations about transports of hazardous goods and, as far as delivery to a repository is concerned, in the emplacement conditions. In addition, other requirements may arise from the permits for interim stores or conditioning facilities. To meet these requirements, German nuclear power plant operators, together with the conditioning facilities and external interim stores, have used the waste flow tracking and product control system, AVK, in an integrated data network, the so-called AVK network, since mid-1991. The contribution contains an overview of the basic features of AVK with a brief historic summary, explains the modifications made in the new Radiation Protection Ordinance compared to the Waste Control Directive as well as its implementation within the framework of AVK upgrading, and also covers the details of the performance characteristics and the spectrum of uses of the current IT code, AVK 3.0. (orig.)