A method and apparatus are disclosed for enabling high-efficiency communication in wireless local area network (WLAN) systems. A station (STA) may receive an Uplink Priority List (UPL) from an access point (AP). In one example embodiment, a STA may send a request for prioritized access to an AP. The STA may then receive an ordered queue of STAs granted contention free prioritized access in a predetermined time interval, which may be referred to as the Exclusive Priority Access (EPA) period. The STA may then determine whether it is identified in the ordered queue of STAs granted prioritized access. The STA may then access a medium such as a Carrier Sense Multiple Access (CSMA) wireless medium associated with the IEEE 802.11 network, in turn with other STAs in the ordered queue per the queue order during the predetermined time interval using an inter-frame spacing, thereby enabling contention free access.