Target wake time (TWT) within single user, multiple user, multiple access, and/or MIMO wireless communications. Within communication systems including different respective devices therein (e.g., wireless stations (STAs), smart meter stations (SMSTAs), etc.), coordination is made with respect to those devices awakening from less than full power state (e.g., from sleep, reduce functionality, power saving state, etc.). A TWT information element (IE) may be included within a frame or a signal corresponding to or based on that frame that is transmitted from one device to other device(s). One or more respective future targeted times (e.g., which may be based on a timing synchronization function (TSF) reference time) at which device(s) may awaken from less than full power state may be included within the TWT IE. Over time, different respective TWT IEs may be provided from various devices, such that respective targeted awake times may be modified dynamically for any given device.