There is provided mechanisms for evaluating co-scheduling of terminal devices. A method is performed by a network node. The method comprises obtaining an indication that a terminal device served by the network node is involved in a data session being longer than a threshold time value. The method comprises initiating, as a result of the data session being longer than the threshold time value, a beam sweep procedure using analog beamforming with the terminal device. The beam sweep procedure results in identification of a set of candidate beams in which the network node is able to serve the terminal device during the data session. The method comprises evaluating whether to co-schedule the terminal device with another terminal device in any of the candidate beams or not. The so-called another terminal device is also served by the network node.