The increasing success of wireless technologies is sustaining the diffusion of mobile information systems, but the youth of the underlying technology and its peculiar characteristics are impacting the development of such systems. For example, the execution of business processes in such a context must cope with the variable and fluctuating bandwidth available to the different devices. This leads the designer to stress the independence of each actor -- by minimizing interactions and knowledge sharing -- to increase the reliability of the whole system.

To this end, the paper proposes a rigorous approach for partitioning the execution of BPEL workflows on sets of portable devices, that is, the infrastructure of mobile information systems. The approach abstracts BPEL processes into attributed graphs and uses a graph transformation system as rules to split single workflows into meaningful sets of related processes. The paper presents such rules and exemplifies them on a case study in the cultural heritage domain.