Leadership is critically important because it affects the health of the organization. Research has found that leadership is one of the most significant contributors to organizational performance. Expanding and replicating previous research, and focusing on the specific telecommunications sector, this study used multiple correlation and regression analyses to demonstrate a significant relationship between leadership styles and organizational performance at a communications company. Validated in the study were the effects of employee job satisfaction and affective commitment on the above relationship. Participated in the Web-based survey were 151 IT knowledge workers from a major communications company in the United States. Quantitative correlational was the research method used in the study. The Multifactor Leadership Questionnaire (5X) Short Form was the major instrument used to measure the predictor variables of transformational, transactional, and laissez-faire leadership. The findings of this study indicated that transformational and transactional leadership related positively and significantly to organizational performance. Transformational leadership was a stronger predictor of organizational performance, satisfaction, and commitment than transactional leadership was. Conversely, laissez-faire leadership had a direct and negative relationship with organizational performance. The empirical results of this study may contribute to the body of leadership knowledge and practice, and provide IT leaders and managers with a new, validated leadership style that is situational, transformational, visionary, innovative, participative, and employee-oriented. Recommended in the study was a new leadership model that includes a new decision-making paradigm. [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.]