The paper focus on the development of building acoustics in Sweden exemplified by the activities at Chalmers University of Technology. Developments are often initiated by incidences where people meet at a place in a certain context. So also happened in Sweden in the middle of the forties when Per Bruel came as refugee from the German occupied Denmark to Chalmers where he started the Chalmers Acoustic Laboratory. He was soon joined by Uno Ingård who later was professor at MIT. At that time Sweden was in a transition process from an agrarian to a highly industrialized nation leading to a large urbanization. Shortage of housing and the need to increase housing standard led to the so-called million program with the goal to build one million flats. New building technologies (e.g. light concrete walls or the use of pre-fabricated elements) as well as the need/wish for cost efficiency led however to buildings of varying quality with new challenges with respect to building acoustics. As consequence building acoustics was identified as important part in the education of civil engineers and in 1962 Chalmers established a professorship in building acoustics. In 1969 Tor Kihlman became the first professor in building acoustics in Sweden.