Adaptive systems should be able to adapt to changes that occur in their operating environment without any external human intervention. Software architectures for such systems should be flexible enough to allow components to change their pattern of collaboration depending on the environmental changes and goals of the system, without changing the actual components themselves.This paper describes a co-operative object-oriented style that is able to represent software architectures for adaptive systems. The connectors in this style, described as co-operations, embody the description of complex interacting behavior between the architectural components.Depending on the environmental changes, the behavioral adaptability in a co-operative object-oriented architecture is achieved by replacing the connectors. The applicability of the architectural style is demonstrated in terms of a case study of a control system that has to adjust the height of a vehicle's suspension to different road conditions.