Strategic information systems planning is the process of identifying a portfolio of computer-based applications that will assist an organization in executing its business plans and realizing its business goals. Carrying it out is a critical challenge for many information systems and business executives. Despite its importance to them, the absence of a theory of strategic information systems planning impedes research in the area. An input-process-output model provides the initial basis for such a theory. Constructs in the final version of a theory are: (1) the external environment, (2) the internal environment, (3) planning resources, (4) the planning process, (5) the information plan, (6) the implementation of the information plan, and (7) the alignment of the information plan with the organization's business plan. The constructs exhibit causal relationships among each other. Hypotheses illustrate the relationships. The theory has value for both researchers and practitioners.
