Embodiments of an access point configured for station group management and a method for managing station-management groups in a wireless network are generally described herein. In some embodiments, the access point may transmit a group allocation message to selected stations and establish a station-management group to include stations from which response frames are received. The access point may also transmit DL MU-MIMO transmissions to the stations of the station-management group using a MU-MIMO technique. When explicit group deletion is employed, the access point may explicitly delete some stations from the station-management group by transmitting a group deletion message to the stations of the group. When implicit group deletion is employed, the access point may implicitly delete some stations from the station-management group after a predetermined period of time indicated in the group allocation message by refraining from transmitting DL MU-MIMO transmissions or group update messages to the stations of the group.