AbstractMaturity models are credited with raising project management awareness, but no conclusive evidence supports their use as a tool for performance enhancement in construction project settings. The present study thus examined the influence of time, cost, and quality management maturity on performance indices of building construction projects in Myanmar. The study further assessed how maturity in time, cost, and quality varied between public and private construction organizations. Four building construction projects, i.e., two operated by private construction organizations and two operated by public construction organizations in Myanmar, have been chosen for the data collection. The project manager and an individual from the upper management of each project were interviewed in three stages to obtain the maturity level. The performance indices of each project were evaluated quantitatively. The study’s findings revealed a positive relationship between project management maturity and project performance. Specifically, a higher time management maturity contributed to greater time performance, and elevated cost management maturity projected higher cost performance. Contrary to the expectations, the study could not find a significant relationship between quality management maturity and quality performance. The results further revealed that the average time management maturity of public construction organizations was significantly higher. Still, the average cost and quality management maturity were considerably lower than that of private construction organizations. The construction organizations aiming to enhance the project performance should focus on reaching a higher maturity in time and cost management knowledge areas.