Strategic information systems planning: The search for an optimal level

Strategic information systems planning (SISP) remains a critical issue for senior business and information systems executives, but both too little and too much SISP might prove ineffective. Hypotheses test the proposed relationship between SISP comprehensiveness and SISP effectiveness in five planning phases. They predict a nonlinear, inverted-U relationship, thus suggesting the presence of an optimal comprehensiveness level. A postal survey of 1,200 U.S. information systems executives produced 161 usable responses. An extensive validation of constructs followed. The statistical analysis supported the hypothesis in a strategy implementation planning phase, but not in four other SISP phases. Managers may benefit from the formal finding that both too much and too little implementation planning may impede SISP success. Future investigators should research reasons that the hypothesis was supported for that phase, but not the others.