Recently, as business becomes more dependent on information technology for their operations, SI project managers are under increasing pressure to implement SI projects on time and within budget, and to satisfy customer requirements. For the success of SI projects and customer satisfaction, SI project managers should master the critical shills and knowledge requirements and consider the proper leadership style to lead the team members and to manage SI projects. The leadership style includes four categories, such as directive leadership, supportive leadership, participative leadership, and achievement-oriented leadership. This study has examined the project managers' competency and suggests the three competency factors, which are technical, human, and conceptual shills, for the success of SI projects and customer satisfaction. The study suggests that SI project managers should master the three critical skills and knowledge requirements, and consider the proper leadership style for the successful implementation of SI projects. Also SI project managers should consider contingency factors such as project size and duration and outcome variables such as protect performance and customer satisfaction so as to enhance the leadership effectiveness.