A wireless LAN environment includes at least one access point that supports a number of wireless communications devices which are configured to operate in the U-APSD mode. The transmission of packets by an access point to a wireless communications device operating in the U-APDS mode can be accomplished in an efficient manner by coordinating the unscheduled service periods of the wireless communication devices. The service periods are placed into a tightly packed list ordered according to a network address associated with each wireless communications device.
