for affecting the actual ep process additional mechanisms are provided to provide feedback to enhance the model and to enhance operation of the ep process the process of modeling is simplified by a unique graphical language disclosed below which permits easy process definition easy editing and simple mechanisms for automatic code generation fig1 presents one view of the disclosed arrangement it comprises a set of tools 20 which receive input signals 22 interact with a data repository 10 and provide output signals 21 elements 10 20 and 40 are supported by an operating system and associated hardware 30 output signals of the tools are applied via bus 21 to a user interface module 40 and to the ep process 50 modules 40 and 50 feed information to tools 10 via bus 22 repository 10 includes objects relationships and properties properties are attributes that can be associated with both objects and relationships the elements of repository 10 are typically implemented via records or lines in tables within repository 10 examples of objects are processes activities applications files people roles resources data data types etc examples of relationships are precedence containment control etc examples of properties are name cost duration size quantity actions etc properties may be mathematical or statistical expressions and they may even be based on other properties element 30 can be a conventional pc or a network of distributed heterogeneous computers unlike in prior art arrangements where a model is fully contained within a single computer file database in accordance with the principles disclosed herein a model or a set of models objects and their relationships may be distributed across multiple heterogeneous file systems and files tool block 20 which interacts with repository 10 comprises a set of tools.