“…An experienced and competent professional project manager can solve frequently encountered causes of delays in construction industry all over the world [61]. The factors of delay in this group are lack of experience construction manager [7,23,36,83], poor site management [17,20,53], contractors' excessive workload [83,86,87], poor contract management [16,18,20,57], conflicts between the parties [4,12,27,34], poor material management [27,53,89], poor coordination among parties [13,17,18,53], contract related dispute/claim [3,17,91], and insufficient communication between the owner and designer in design phase [4,13,84]. Among these factors, poor coordination and communication, and poor site management are found as most frequent causes in all the regions.…”