To achieve high throughput in wireless networks, collision rate must be very small, while communication overheads (e.g., RTS/CTS dialogues) and channel idleness (e.g., due to backoff) should be both relatively small as compared to data packet durations. Low collision rate is also essential to QoS provisioning in any network employing exponential backoff or a similar strategy. Our proposed solution to the preceding contradicting requirements is to employ prohibition-based mechanisms, which replace the functionality ofRTS/CTS dialogues that have been shown to suffer from high communication overhead but only provide limited protection against the hidden terminal problem while in multihop networking environments. The resultant prohibition-based MAC protocols combine binary countdown with busytone, thus inheriting important advantages from both worlds including collision freedom/controllability, prioritization capability, and elimination of hidden terminals. They can also support asynchronous operations which are of practical importance.