To allow for flexibility in software structures (architectures) especially plugins and agents are proposed solutions. While plugins are used to support the conceptual and practical issues within component oriented software environments, agents are used in software areas where social metaphors like (self-)adaptability, flexibility, mobility, interactivity etc. are of interest. Common to both approaches is a strong relation to a service-oriented view on exporting functionality. This contribution illustrates the idea of the integration of both concepts on the formal basis of high-level Petri nets.