Abstract— Our approach to the model-driven collaborative design of workflows for bioinformatic applications uses the jABC [6] for model driven mediation and choreography to complement a Webservice-based elementary service provision. jABC is a framework for service development based on Lightweight Process Coordination. Users (product developers and system/software designers) develop services and applications by composing reusable building-blocks into (flow-)graph structures that can be animated, analyzed, simulated, verified, executed, and compiled. This way of handling the collaborative design of complex processes has proven to be effective and adequate for the cooperation of non-programmers (in this case biologists) and technical people, and it is now being rolled out in the operative practice. I. THE SETTING: DISTRIBUTED BIOINFORMATIC WORKFLOWS