Abstract: Methods, systems, and computer program products for assigning seats of passenger-transport vehicles to passengers. The passengers are subdivided into a plurality of groups. The passengers included in each group are connected by social-network relations and have less than a maximum number of social-network relations to other passengers outside of the group. Breaks of the social-network relations between the passengers are minimized when the passengers are subdivided into the groups. In response to one of the passengers being excluded from the groups, one of the groups is determined that includes at least one included passenger with at least one of the social-network relations to the excluded passenger to thereby increase the size of the group by adding the excluded passenger.