The present invention discloses a method for positioning signal sources in a wireless network, e.g. in a WLAN or WiMAX network. The located signal source might be a end user, an interfering source or a base station. At least one monitoring station is placed in the network, which use directional antennas. By combining e.g. the direction of the used antenna beam, the received relative signal levels, propagation delay measurements and several different measurement locations for one or several monitoring stations, the location of the signal source can be determined accurately. The method can also track whether the end user is connected to the most optimal base station by transmitting test signals through base stations.