The current premise in the enterprise architecture (EA) literature is that business architecture defines all other EA architecture layers; information architecture, information systems architecture, and technology architecture. In this paper, we will study the ICT-cooperation between eight small and mid-sized municipalities and cities in Southern Finland. Our case demonstrates that the ICT-cooperation is possible without business cooperation and that ICT-cooperation can be a driver for future business cooperation. The findings challenge the current premise of the guiding force of the business architecture and encourage organisations’ ICT-functions to seek daringly cooperation with other organisations.