Abstract: Over an open and dynamic networked environment filled with heterogeneous services, a challenge issue to be coped with, whenever constructing services oriented collaborative organizations, is the complicated social interactions among autonomic service agents. An extended reference Petri net (called deontic Petri net, DPN) was proposed, which incorporates the role and norm concepts of organizational modeling with the concepts of net within net and synchronous channel in reference net model. The modeling and analyzing methods toward collaborative interactions among service a- gents with DPN were presented. An electronic institution model was applied to demonstrate the advantages of DPN and a case study shows the usefulness of the presented approach.

Key words: Collaborative interaction, Petri net, Modeling, Deontic norm