This two-part thesis examines the routing and MAC protocols for Mobile Ad hoc Networks (MANETs). First, we study the performance of the Ad hoc On-demand Distance Vector (AODV) routing protocol in Riverbed Modeler. We examined avenues to improve the performance of AODV for the scenario we modelled by trying to correct all the avoidable events that would affect the network performance. Shared media access is complicated. The family of medium access control (MAC) protocols is an important factor in design and modelling of the network. The challenge of employing a MAC protocol that is not wasteful of network resources but at the same time is flexible in accommodating multiple nodes contending for the channel is a significant one. The second part of the thesis is the development and implementation of a decentralized MAC protocol for MANET called SEEDEX, that gives each node intending to use the channel an equal opportunity to do so while avoiding making explicit reservations. The protocol does not silence the neighbor nodes during an ongoing transmission and still manages to achieve low latency. The protocol is self-configuring and scales well as the network size increases.