This paper presents a simple wireless medium access control (MAC) protocol that facilitates wireless nodes’ cooperatively scheduling their use of the wireless medium. With this protocol, wireless nodes can pre-plan their active and inactive periods. Nodes can also change their schedule cooperatively as data generation and required data flows change. Such planning and adaptation can significantly save energy consumption by nodes going to sleep mode during inactive periods. Features of this protocol include synchronizing superframes of time slots by all nodes, distributed scheduling of packet transmissions, and each node maintaining its own neighborhood map. A node’s neighborhood map records current schedules of medium access by neighboring nodes, namely, which nodes are scheduled to use which time slots for what purpose. The use of neighborhood maps prevents packet collision and also allows spatial re-use of the same time slots for spatially far apart nodes. We discuss the presented protocol’s ability to avoid packet collision and the hidden node problem. We also analyze the protocol’s performance in the case of asymmetric wireless channels.