One of the most common concern in construction projects is changes during execution. Changes can increase the cost and duration of the construction project hereby, can lead to conflict between the parties involved in construction projects. Causes of the changes may differ depending on the organizations and regions characteristics. The aim of this study is to investigate the impact of organizational and regional characteristics on key change factors. In this regard, top risky change factors were identified with respect to contractors, consultants, and owners located in North Cyprus, Turkey, and the U.S.A. The research findings showed that the most risky change factors differed in accordance with the characteristics of organizations and regions. It was concluded that "Errors/Inadequacies in Contract Drawing" was the riskiest factor according to contractors while "Low price due to high competition" was noted to be the riskiest change causes with respect to consultants and owners. If different countries were compared, "Inconsistency between different design disciplines" was identified as the top risky change factor according to the respondents in the U.S.A. located organizations, but "Low contract price" was designated as the top risky change factor according to the respondents in North Cyprus and Turkey. In addition, key measures were suggested to mitigate changes in accordance with organizational and regional characteristics.