In today’s competitive business, buying and returning products have become a common practice because of incompleteness of the products or its failure to meet the customer’s satisfaction or reusing products. Before this cycle can be handled, companies need a proper logistics network because of its impact on the efficiency and responsiveness of the supply chain. In this research, a forward and reverse logistics network is proposed for product distribution and collection. The contribution of this paper is the proposal of a multi-period, multi-echelon integrated forward and reverse supply chain network design problem with transportation mode selection. Different decisions including determination of optimum number and locations of facilities, facilities opening time and transportation mode selection have been considered in this paper. Due to multi-period nature of the problem, the problem is flexible for future periods. A mixed integer nonlinear programming model proposed for the introduced problem considering levels of facility capacities. As another contribution, a genetic algorithm developed to cope with problem’s complexity especially for large size instances. Effectiveness and reliability of the algorithm evaluated by solving several random instances, with the obtained numerical results and comparisons confirming capability of the proposed algorithm for finding good solutions within acceptable processing times.
