Traditional process support systems offer the promise of software assembled from service elements. The typical approach is a static composition of atomic processes to more powerful services. In the real world, however, processes change over time: business needs are rapidly evolving and, thus, changing the work itself and relevant information may be unknown until workflow execution run-time. Hence, the traditional, static approach does not sufficiently address the need for dynamism. Based on applications in the life science domain this paper puts forward five requirements for dynamic process support system. Specifically, these demand a focus on a tight user interaction in the process discovery, composition, and execution phases. The system and the user establish a continuous feedback loop resulting in a mixedinitiative kind approach. We also present a prototype implementation NExT, which embodies this approach and present a preliminary validation based on a real-world scenario as well ...