Selection of the most suitable business partner is a strategic decision for outsourcing problems. This study aims to provide an effective evaluation approach for assessing alternative CRM partners. The choice of a suitable partner is a very complex decision, involving many conflicting objectives as well as complex considerations. Such decision processes involving several perspectives can be worked around by using Multi Criteria Decision Making (MCDM) techniques. MCDM can assist decision makers with reaching consensus with collective participation and objective decisions based on value judgments. This paper proposes a combined approach for effectively evaluating CRM partners that integrates Intuitionistic Fuzzy Sets (IFS) with Group Decision Making (GDM). It consists of Intuitionistic Fuzzy Analytic Network Process (IF-ANP) for building and analyzing the criteria weights and Intuitionistic Fuzzy Decision Making Trial and Evaluation Laboratory (IF-DEMATEL), a useful technique for managing uncertainties to identify interrelations between criteria. As the IFS describe powerfully vagueness and uncertainty, IFS can depict decision makers' evaluations with a structure which is more rich, allowing for a more accurate description of the decision making process. The scientific value of the paper stems from its ability to present a novel study that makes use of GDM based MCDM with combined IF-DEMATEL and IF-ANP approaches. This study contributes to the existing literature by providing a combined IFS based DEMATEL-ANP framework for the first time and developing a novel evaluation model for a real industrial problem to improve the CRM partner selection process.