Examples described herein provide multi-band directional scanning. Examples may include receiving, by a first radio of a first network device operating at a first frequency band below the millimeter-wave (mmWave), a probe request from a second network device indicating a protocol and a particular sector receiving direction of the second network device, and in response to the protocol indicated by the probe request, transmitting, by a second radio of the first network device operating at a second frequency band within the mmWave, a probe response in each of one or more sector transmitting directions, wherein the second network device receives one or more probe responses in the particular sector receiving direction.