A method for communicating an acknowledgment policy for a data unit in a wireless local area network is described. A plurality of medium access control (MAC) protocol data units (MPDUs) of an aggregate MPDU intended for a second communication device are generated. A plurality of MPDU delimiters are generated, each MPDU delimiter of the plurality of MPDU delimiters indicating an acknowledgment policy for a corresponding MPDU of the plurality of MPDUs. At least two MPDUs of the plurality of MPDUs correspond to MPDU delimiters that indicate an acknowledgment policy corresponding to a single acknowledgment frame for the corresponding MPDUs. The aggregate MPDU is generated to include the plurality of MPDUs and the plurality of MPDU delimiters. The aggregate MPDU is caused to be transmitted from the first communication device to the second communication device.