A first access point (AP), which is associated with one or more first client stations, receives an announcement frame from a second AP that is associated with one or more second client stations. The announcement frame announces a coordinated multi-user (MU) transmission involving at least the first AP and the second AP, includes an indicator of a frequency resource unit (RU) allocated to the first AP for the coordinated MU transmission. The first AP participates in the coordinated MU transmission using the frequency RU indicated by the announcement frame while the second AP also participates in the coordinated MU transmission.