Modern software systems share with social organizations the attributes of being large-scale, distributed, and heterogeneous systems of systems. The organizational metaphor for software engineering has particularly been adopted in the field of multi-agent systems but not entirely exploited due to an inherent lack of collective levels of action. We propagate a shift from multi-agent to multi-organization systems that we rest upon an organization theoretically inspired reference architecture. We further suggest to ultilize agent-oriented technology as a means for realization. We draw upon the wide variety of organizational modelling and middleware approaches and establish a best fit between different approaches and and requirements for different architectural levels.