Chief Information Officers (CIOs) lead enterprise information technology organizations (EITOs) in today's dynamic competitive business environment. CIOs deal with external and internal environmental changes, changing internal customer needs, and rapidly changing technology. New models for the organization include flexibility and suggest that CIOs should create and manage an enterprise IT organization that is more flexible in order to manage change and prepare for uncertainty, but they do not define what is meant by flexibility. The first objective of this exploratory and ethnographic research study was to understand how uncertainty and unexpected change are currently managed by CIOs. The second was to develop a systematic definition of enterprise IT organizational flexibility. The third was to explore the potential value of a proposed 'enterprise IT organizational flexibility framework' to be used by CIOs to better manage uncertainty and unexpected change. Rich research data was collected in an exploratory ethnographic study from in-depth interviews with twenty CIOs. These participants included a diverse representation from large to small enterprises, different industries, and with a variety of IT education and functional enterprise experiences. The conclusions from this study included a clearer understanding of the CIO's leadership role when managing uncertainty and unexpected change, a definition of enterprise IT organizational flexibility with three aspects: anticipation, agility, and adaptability, and a framework for enterprise IT organizational flexibility assessment and development. [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.]