Mirja Pulkkinen's PhD thesis, 2008. The information and communication technology (ICT) advancements change the role of ICT in organizational use to a central concern, since both business and public enterprises heavily depend on information systems and technological infrastructure. Management, planning and development of the organizational ICT are no more a task for the ICT experts only. The expertise of both business and ICT specialists is needed to align ICT deployment with organizational goals, ensuring appropriateness of related investments with respect to the enterprise resources. However, collaboration between the business and ICT communities of practice is perceived as a challenge. Enterprise architecture (EA) proposes a holistic approach to the management of organizational ICT systems and infrastructure. By structuring the collaboration, it interlinks the contributions from different communities of practice to the decision making process. From both IS and EA literature, a common framework of reference is derived and validated through practitioner experience. Distinct levels of abstraction in the framework accommodate the concerns of different decision makers: managerial overview for the whole enterprise, business operations management at the level of the activity domains, and the systems design and development concerns for the implementers. An understanding of the ICT management and planning in the context of a deploying organization is deduced as a prerequisite for an eligible EA methodology. An EA process meta-model is constructed to guide the overall EA process for well-informed strategies and decisions on the organizational ICT and, as well, for consulting assignments. The study is conducted as an action research effort within an ICT consultancy, for which it develops an EA methodology. Case studies of client projects in different industry domains and various types of organizations provide the empirical basis. The constructed results are validated in practical use along the research effort. Reflective analysis of the series of studies reported on academic fora conveys a discursive process. Establishing a common agenda and giving empowered roles for different expert groups characterize both the research process and the EA process meta-model that logically guides and coordinates the dynamics of the collaborative enterprise development.