1 Dynamic Changes in Workflow Participant Assignment 1 Mariusz Momotko * and Kazimierz Subieta +# *) Rodan Systems S.A., Warsaw, Poland +) Institute of Computer Science PAS, Warsaw, Poland #) Polish-Japanese Institute of Information Technology, Warsaw, Poland Abstract Workflow management systems (WFMSs) need to adapt dynamic process modifications. In current WFMSs the scope of dynamic modifications is mainly focused on control flow while other dynamic aspects, such as workflow participant assignment (WPA), are neglected. In this paper an approach to adapt dynamic modification in WPA is presented. The approach extends the meaning of WPA that is proposed by the Workflow Management Coalition. The extension covers dynamic aspects and express complex relationships between control, audit and relevant data. On basis of the new definition a WPA Language (WPAL) is proposed. WPAL is a programming interface, which makes it possible to assign dynamically workflow participants. WPAL is implemented in OfficeObjects ® WorkFlow and deployed in several major customers of the Rodan Systems. The paper presents implementation results. 1. Introduction Nowadays organisations to be competitive and to play the leading role on the market need innovative and efficient business processes. A workflow management system (WFMS) is frequently used as a supporting tool. A business process is represented in WFMS as a workflow process (referred further to as workflow). WFMSs enable workflows to be designed, executed, monitored and optimised. A workflow consists of activities, which are units of works. The order of performing activities is determined by transitions in a workflow specification. An activity is to be performed by one or more workflow participants. The main goal of a workflow is to assure that a given activity will be performed by the right workflow participant in due time. A desirable feature of the workflow technology is its adaptability to workflow changes that can occur during a workflow execution (referred further to as dynamic modification). Such a feature is especially important for real-life workflows that can be changed frequently to adapt changes of the workflow environment, for instance, department reorganisation, absence of a workflow participant, unavailability of a printer, and so on. Dynamic workflow modifications, depending on their durability, is one of the following types: • Modification of an executed workflow (referred further to as workflow instance). The modification concerns some workflow instances and usually is connected with transient changes or exceptions. • Modification of a workflow definition. It concerns all workflow instances and usually is connected with workflow optimisation. Information on how a workflow has to be modified can be achieved on the basis of: • Control data representing the dynamic state of workflow instances and the WFMS (e.g. workflow definitions); 1 This work is a part of the EU 5 th Framework project ICONS (Intelligent Content Management System), IST-2001-32429.