[en] The principles of the representation of dynamic data structures within the modular system RSYST-II are described. The identification of data blocks and data elements is carried out with the help of hierarchical data structures. Therefore, a simple formulation of complex burn-up problems is possible. The scheme of identification permits the user to define table functions simply. The consequent application of this scheme leads to a general generation and representation module for different data block types and to a data-structure independent programming of modules. (orig.)