Service-Oriented Computing and Agent Technology are nowadays two of the most active research fields in distributed and open systems. However, when trying to bridge the two worlds, it becomes apparent that the interaction-centric approach of multiagent systems may affect the way services are modelled and enacted, and vice versa. We claim that organisational models that underlie multiagent interactions are crucial in order to take advantage of this interrelation. In this paper we present an approach for modelling organisational structures in service-oriented multiagent systems, and show how it affects semantic service descriptions. We also present approaches to service matchmaking as well as to service composition, capable of exploiting organisational information in service descriptions. In both cases, we prove experimentally the validity of our approach. Categories and Subject Descriptors I.2.m [Artificial Intelligence]: Miscellaneous General Terms Algorithms, Design. Keywords Semantic...