Information Technology Governance (ITG) is among the most important challenges for the managers today. IT is not anymore just a supportive tool but also a strategic driver for the businesses. In the dynamic and competitive world of today, it is crucial for organizations to know how to govern IT rather than just to use it. IT governance deals with specifying responsibilities and decision rights to encourage the desirable behaviour from IT and generate value from IT investments. IT governance can impact the overall performance of organizations, however there are still difficulties in understanding IT governance and the factors that may influence it.

Organizational culture and structure are among the factors that have significant influence on many issues in an organization. According to previous research, organizational culture and structure need to be considered when implementing IT governance. However, there is a lack of research focusing on how organizational culture and structure can influence IT governance performance and implementation. Thus, the main research question addressed in this thesis is: How are organizational culture and structure related to IT governance? To address this question, this research has performed literature reviews and conducted case studies to investigate the role of organizational culture and structure on IT governance. As the first step, the previous literature was reviewed to find the gaps in the research on culture and IT governance. As the next step, four case studies were conducted to explore the influence of organizational culture and structure on IT governance. Two case studies have investigated the relation between organizational structure and IT governance implementation and performance in large organizations; and two other case studies investigated on how different types of organizational culture influence IT governance performance outcomes.

The results of this research respond to the research question by specifying the role of culture in IT governance through a categorization of prior research both from research and practice perspectives; specifying the influence of different organizational culture types on IT governance performance outcomes in different organizations; and by specifying IT organizational structure relationship with IT governance performance outcomes and IT governance implementation.

The research presented in this thesis provides both theoretical and empirical contributions to the IT governance research and practice.