Information systems plans traditionally have been conceived as a means of recognizing opportunities and problems where information technology might be used, identifying the resources needed to support the application of information technology, and developing strategies and procedures to allow information technology to be applied successfully. From an agency theory and transaction cost theory perspective, however, information systems plans might also be used to provide a basis for bonding and monitoring information systems managers, to help resolve how unforeseen gains and losses will be distributed among information systems managers and their superiors, and to facilitate judgments on the level of decision rights to be delegated by senior management to information systems managers. In the context of this latter view of information systems planning, an important issue is to understand the set of factors that determine whether senior management or the information systems manager controls the planning process and whether the focus of the plan primarily addresses the goals and objectives of senior management or the information systems manager. We propose a model that articulates how information technology infusion and diffusion might impact who controls the planning process and ultimately the focus of the plan. We then test this model empirically using a survey of information systems managers and their i:mnediate superiors. We find that higher levels of infusion are associated with senior management exercising greater control over the planning process and the plan focusing more on their goals and objectives. Diffusion also has an impact on these two variables via its effects on infusion.