In the current era of accelerated economic growth, project success – successful completion of the final product for which the project was initiated – is the ultimate goal of every organisation. It is essential for organisations to keep project-based employees motivated and focused on successfully accomplishing the project objectives. This research examined the association between psychological empowerment of project-based employees and project success. We explored the mediating role of knowledge sharing to explain the intervening mechanism between psychological empowerment and project success. We also tested the moderating role of employee creativity along with conditional indirect effects by performing a moderated mediation analysis. Using a time-lagged research design, multiple-source field data (N = 327) were collected from employees of project-based organisations in Pakistan. The findings of the study showed a positive association between psychological empowerment and project success and significant mediation of knowledge sharing. Project employees with high creativity are likely to achieve project success when they possess higher psychological empowerment too. Results concluded that psychological empowerment is positively associated with project success directly as well as indirectly through its impact on knowledge sharing. The study has its importance and implications for management specialists and project employees at all levels.