en تحقیق در عملیات Operations Research پژوهشي Research Decision making about outsourcing or insourcing of manufacturing activities is a type of multiple criteria decision making (MCDM) problem, which requires considering quantitative and qualitative factors as evaluation criteria simultaneously. Therefore, a suitable MCDM method can be useful in this area as it can consider the interactions among quantitative and qualitative criteria. The analytic network process (ANP) is a relatively new MCDM method which can deal with different kinds of interactions systematically. Moreover, the Decision Making Trial and Evaluation Laboratory (DEMATEL) method is able to convert the relations between cause and effect of criteria into a visual structural model as well as handling the inner dependences within a set of criteria. However both ANP method and DEMATEL techniques in their original forms are incapable of capturing the uncertainty during value judgment elicitation. To overcome this problem, here, a new and effective model is proposed based on combining fuzzy ANP and fuzzy DEMATEL for decision making about outsourcing or insourcing of manufacturing activities in uncertain conditions. Data from a case study is used to illustrate the usefulness and applicably of the proposed method. Outsourcing, Triangular fuzzy number, fuzzy ANP, fuzzy DEMATEL 163 174 http://ijiepr.iust.ac.ir/browse.php?a_code=A-10-149-2&slc_lang=en&sid=1 mahdi Yousefi nejad attari mahdi_108108@yahoo.com 180031947532846001900 180031947532846001900 Yes mohhamad reza bageri 180031947532846001901 180031947532846001901 No ensiyeh neishabouri 180031947532846001902 180031947532846001902 No