With today's increasingly competitive economy, many organizations have initiated customer relationship management (CRM) projects to improve customer satisfaction, revenue growth and employee productivity gains. However, only a few successful CRM implementations have successfully completed. In order to enhance the CRM implementation process and increase the success rate, in this paper, first we present the most significant success factors for CRM implementation identified by the results of literature reviews and a survey we conducted. Then we propose a strategy to integrate Six Sigma DMAIC methodology with the CRM implementation process addressing five critical success factors (CSF). Finally, we provide a case study to show how the proposed approach can be applied in the real CRM implementation projects. We conclude that by considering the critical success factors, the proposed approach can emphasize the critical part of implementation process and provide high possibility of CRM adoption success.