The business and Information Technology (IT) alignment issue has become one of the Top-10 IT management issues since 1980. IT has continually strived to achieve alignment with business goals and objectives. These IT efforts include ERP implementation to benefit from the best practices; data center consolidation and server virtualization to keep costs down; data warehouses and business intelligence to provide data with better quality; COBIT to provide IT regulation and control; ITIL to address IT operations; as well as Enterprise Architecture (EA) to provide the foundation of IT in an organization. EA has been extensively covered in the past two decades with most of the efforts focusing on Technology Architecture, Information Architecture and Application Architecture and less emphasis on Business Architecture (BA). This research developed a comprehensive Business Architecture methodology to address and improve Business and IT alignment. The research is based firstly on the proposition that a comprehensive Business Architecture is required to enhance Business IT alignment. The second proposition states that Business Architecture development must be done before the development of Information Architecture, Application Architecture, and Technical Architecture. A thorough literature review was performed on topics of business situations, enterprise strategy, IT strategy, existing theories of EA, EA development approaches, famous EA frameworks, the existing theories of Business and IT alignment as well as the current development state of BA. This research has resulted in the development of the conceptual solution of the BA Development Approach, and used to validate the research propositions. The conceptual solution encompasses the BA principles, BA sub-viewpoint, BA framework, BA process model and BA methodology. The conceptual solution was validated using a qualitative research methodology and a case study performed in an actual manufacturing company. The key contribution of this research is that it has demonstrated that the business can greatly benefit from the development of the Business Architecture that provides improved alignment with the IT processes. The improvements are mainly achievable in the communication and partnership perspectives. The Business Architecture should be implemented before other architectures. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]