Services are increasingly becoming the building block of today's distributedsystems. However, to support the development of robust complex applications made up ofensembles of cooperating service components and to promote autonomic features(i.e., self-management and self-adaptation), adaptive collaboration patterns among components have to be enforced. In this paper, to analyze adaptive collaboration patterns in agent-based terms,we would like to introduce a taxonomy of adaptive agent-based collaborationpatterns, for their exploitation in the area of autonomic service ensembles. The proposed taxonomy, as preliminary as it can be, has two main advantages: (i) it enables the reuse of existing experience from the agents' world in the area of autonomic service systems, and (ii) it can provide useful suggestions to designer for the choice of the most suitable patterns.