This study surveyed 497 project management software users in a wide variety of project-driven organizations to examine the relationships among: computer self-efficacy, information quality, system functionality, ease of use, project complexity, performance impact, organization size, project size, and user education, training and experience level. The findings indicated that information quality and project complexity are the dominant factors in explaining the levels of perceived system utilization; system functionality and ease of use have a significant effect on software usage; and that a strong relationship exists between perceptions of usage of software and project managers' performance. Inconsistent with prior research, training level was found to have no influence on project management software usage. However, software experience and education level had a moderate effect on the use of the software. Both organization size and project size had significant effects on the use of the software.