This study aims at differentiating construction project critical success factors based on organizational backgrounds of project participants: contractor, construction manager (owner representative), and design firms. Construction professionals from diverse locales were asked to rate a list of 53 potential factors for the objectives of schedule, budget, and quality, and additionally compare the objectives for overall project success. The set of 53 factors was enriched by eliminating 13 factors that could not prove their statistical significance for even one of schedule, budget, or quality performances for any of the three organizations. Commissioning the 40 significant factors, an analytical hierarchy process was used to determine organization-based factor rankings for overall project success. Spearman's test on rankings of the 40 significant factors for overall project performance results in a highest level of correlation between the managers and contractor personnel (r(s) = 0.54), followed by that between the managers and the designers (r(s) = 0.50), and a least correlation between the contractor personnel and the designers (r(s) = 0.19). Hence for successful project implementation, professional construction managers have an edge over the designers in supervising the contractors. (C) 2014 American Society of Civil Engineers.