Architectural acoustics design has in the past been based on simple design rules. However, with a growing complexity in architectural acoustics and the emergence of room acoustic simulation programmes with considerable potential, it is now possible to subjectively analyse and evaluate acoustic properties prior to the actual construction of a building. With the right tools applied, acoustic design can become an integral part of the architectural design process. The aim of this paper is to investigate the field of application that an acoustic simulation programme can have during an architectural acoustic design process and to set up a strategy to develop future programmes. The emphasis is put on the first three out of four phases in the working process of the architect and a case study is carried out in which each phase is represented by typical results – as exemplified with reference to the design of Bagsvaerd Church by Jørn Utzon. The paper discusses the advantages and disadvantages of the programme in each phase compared to the works of architects not using acoustic simulation programmes. The conclusion of the paper points towards the need to apply the acoustic simulation programmes to the first phases in the architectural process and set out a reverse strategy for simulation programmes to do so – from developing acoustics from given spaces to developing spaces from given acoustics.