Javad Eskandari Khoee - MSc in Marketing and E-commerce, Industrial Engineering Dept, Tarbiat Modares University
Amir Adnan Sepehri - MSc in Marketing and E-commerce, Industrial Engineering Dept, Tarbiat Modares University
Peter Naudé - Professor of Marketing, Manchester Business school
Mohammad Aghdasi - Associate Professor, Industrial Engineering Dept, Tarbiat Modares University

By utilizing the conceptual framework of the Interaction Approach [1,2,3], this paper investigates purchasing of business services in four Iranian companies, which directly or indirectly are undercontrol of the government. In addition, we investigate the structure of the Decision Making Unit(DMU), the type of services and their effect on purchasing, the effect of price on DMU structure,and the extent of centrality in the governmental organizations. The results show that the level ofvertical involvement depends on expenditure of services, urgency of services, and change offunctional disciplines. The level of connectedness, centrality, and extensivity are not related to thecomponent or consumption services. There is no significant difference between componentservices and consumption services. Moreover, the level of vertical involvement is higher forexpensive services. In addition, the level of connectedness of DMU will be high for expensiveservices. Finally, the centrality of purchasing managers is low in governmental organizations

business services, purchasing, decision-making unit, governmental organization