While IT decision-making was previously driven entirely by the CIO, the CIO-centered IT governance model is no longer appropriate given the increasing IT risks that can seriously harm organizational performance and the growing need to align business strategy with IT strategy, which has heightened interest in the authority and responsibility of IT decision-making. Although recent studies have stated that IT governance is the responsibility of the board of directors and executive management, there is a lack of empirical research on how board participation in IT governance actually affects organizational performance. The legitimacy of board participation in IT decision-making can be supported from the perspectives of agency theory and strategic choice theory. Specifically, agency theory addresses risk management aimed at preventing shareholder losses caused by poor decisions triggered by management incompetence, negligence, or misconduct, while strategic choice theory examines the business-IT alignment perspective in which the board participates in strategic decision-making to enhance shareholder interests. As such, the board's participation in strategic IT decision-making directly affects business-IT alignment and information systems risk preparedness, ultimately influencing information systems effectiveness and business performance. In this study, organizational performance is captured through information systems effectiveness and business performance, both measured using non-quantitative, perceptual measures as perceived by CIOs and business executives. Subjective measurement methods are commonly used when measuring strategy-related performance. For this study, a survey was administered to one CIO and two business executives per firm. A total of 1,470 questionnaires were distributed from October 23 to November 30, 2006. By December 1, 285 questionnaires had been returned, of which 271 were valid. Respondents comprised 105 CIOs (38.7%) and 166 business executives (61.3%). Analysis by firm revealed that at least one questionnaire was received from a total of 110 firms. An independent samples t-test was conducted to check for response differences between CIOs and business executives, but no significant differences were found. PLS was used as the analysis method, with PLS-Graph 3.0 as the analytical tool. In summary, the board's participation in strategic IT decision-making influences IT governance factors—namely, business-IT alignment and information systems risk preparedness—which in turn positively affect information systems effectiveness and subsequently business performance. The expected contributions of this study are that it not only extends IT management within the information systems domain to an IT governance perspective, but also confirms that board participation in IT decision-making contributes to improving firm performance, thereby suggesting future directions for corporate strategy.