Cooperative Information Systems

Conventional work ow functionality like task sequencing split parallelism join synchronization and iteration have proven e ective for business process automation and have widespread support in current work ow products However newer requirements for work ows are en countered in practice opening grave uncertainties about the extensions for current languages Di erent concepts although outwardly appear ing to be more or less the same are based on di erent paradigms have fundamentally di erent semantics and di erent levels of applicability more specialized for modeling or more generalized for work ow engine posit By way of developmental insight of new requirements we de ne work ow patterns which are described imperatively but independently of current work ow languages These patterns provide the basis for an in depth comparison of work ow management systems As such the work reported in this paper can be seen as the academic response to evaluations made by prestigious consulting companies Typically these evaluations hardly consider the work ow modeling language and rout ing capabilities and focus more on the purely technical and commercial