Integration and Collaboration Based on Graphical Techniques (Editorial)

Graphic and diagrammatic techniques have always been very popular for defining and communicating software system properties. Engineering in general has a whole body of drawing techniques to design complex systems. In software engineering research and practice tried to emulate these drawing techniques and early approaches like ER and SA diagrams1) are still in use today. Recently object orientated analysis and design has lead to numerous similar graphic notations where we now observe UML (Unified Modelling Language) as a kind of industrial standard being established. Despite their popularity within the software and requirements engineering communities such diagrammatic description techniques are also disqualified by regarding them at most semi formal or even up to interpretation by the reader. This feature regarded by some as a virtue make these obviously useful techniques not applicable in the context of critical work like flight deck management systems, automatic rail road crossing or medical applications. The current lively discussion wrt. a formal basis for UML shows need and the difficulties arising in such a problem area. However, looking into the detail of the actual problem it is revealed that there is a small number of problems with graphic / diagrammatic description techniques: