This study proposes a methodology for systematically evaluating the project management maturity of business organizations. The methodology is used to quantitatively analyze and compare the efficiency of project management across organizations. A five-level project management maturity model was developed to assess and compare the modern project management stages of business organizations. The study involved thirty-eight companies from abroad, including fifteen engineering and construction firms, ten information and telecommunications companies, ten software companies, and three high-tech manufacturing firms. The study also developed and presented a methodology for calculating the approximate return on investment of project management. First, regression analysis demonstrated a positive relationship between an organization's project management maturity level and its actual cost and schedule performance. Second, based on the regression analysis results, a method for calculating project management return on investment was presented to enable managers to invest in project management and promote the use of its processes. The most significant contribution of this study lies in presenting an objective analytical methodology that allows for the comparison and analysis of project management performance by industry and by organization, thereby enabling project managers and top executives to widely promote and further improve project management processes and efficiency.