Routing Protocols plays crucial role in every field of computer science from internet to mobile phones is dependent on the routing protocols for proper communication & information exchange. In this book implication of two different branches of Computer Science is presented. By the use of Fuzzy Logic performance of OLSR protocol one of the Routing Protocols for MANET is improved. Mobile ad hoc network, the future of networking. It is a collection of mobile nodes without any fixed infrastructure, non centralized control & dynamic topologies. The MANET consists of a large number of nodes having dynamic topology structure, limited power & bandwidth, mobility and connected in an arbitrary fashion through a wireless link. In the MANET environment to make the multi-hop communication possible it is required that participating nodes must communicated & cooperate in an efficient way.The aim of this book is to apply the fuzzy logic on the OLSR protocol one of the routing protocols for MANET and then do the performance analysis of the proposed approach.