This paper presents a Reputation-Trust (RT) system that can be used to stabilize the performance of the network for the working nodes even in the presence of malicious nodes which intentionally do not route and forward packets send by others correctly. The situation becomes even worst when nodes do not rely on any routing infrastructure but relay packets for each other. We introduce two extensions to the Dynamic Source Routing algorithm (DSR) to mitigate the effects of routing misbehavior: the watchdog and the pathrater. Using these two approaches, the proposed RT system will update the RT table of each node with the ranked values of other nodes. The implementation of the proposed RT system is entirely based on the underlying proposed RT algorithm. Simulation results demonstrate that the RT system can be used to reduce the malicious behavior of mobile nodes and consequently improve the overall performance of MANET.