This thesis discusses the efficiency of the Al-Mawaleh Central Market for Fruits and Vegetables using a Transaction Costs (TC) Approach. It deals with some aspects of the marketing problems facing certain players in the fruits and vegetables wholesaler market such as farmers and traders. The approach used stems from the theory of institutions and human behavior that include time and costs of negotiation, monitoring and the various enforcements activities. The thesis attempts to use systematic designs to collect and analyze the multiple relationships which exist among the various players and how the different agents respond to the issues relating to the market. A comprehensive analysis was performed using the Delphi method to analyze stematically a structure of information provided by a group of individuals to classify and establish a consensus on agricultural marketing activities and to show that the efficiency of marketing channels depends on transaction costs. Therefore, some variables were identified and then measured on a five point scale basis through the use of questionnaires which were focused on four main issues: market management, importers, retailers and re-exporters. The objective is to build a database on the players perception. Due to the complexity of the phenomena a model had to be formed to best suit and forecast the major uncertainty of the market environment and act as a basis for future research and progress. Finally, this thesis presents a set of recommendations and conclusions which show that the most successful markets are those with the minimum transaction costs. Also, this thesis recommends that additional future research should be conducted and negotiations at all levels should be initiated in order to reach a better working environment for all players involved in the Al-Mawaleh Central Market including the administration, importers, wholesalers and retailers, and thus reduce transaction costs and maximize market efficiency.