Energy efficiency is one of the major issues in WSANs, mainly because both sensors and actuators are usually battery operated. In order to minimize battery power consumption and maximize the network lifetime, it is essential to have energy efficient communication and energy efficient actuation. The communication cost for the coordination among actuators should be minimized for several other reasons. The wireless medium is shared, so the multiple synchronous messages can cause collisions. Large actuator multi-hop network may pose scalability issues and significant delay in making action decisions, unless the coordination protocols are carefully tailored to the application, energy and time constraints.