"staircase" reflects the transitional nature of the space augmenting it auditorily. Conceived as a permanent installation, it has been carefully embedded into the existing acoustic ecology of the space it inhabits. Operating in its own sound niche, it slightly colours the everyday experience of the people frequenting the building. In its sonic and visual appearance, it is intended to be perceived as an integral part of the building, contributing to its identity and atmosphere. To adapt to the current acoustic situation, which depends on the number and behaviour of the people frequenting the building, the installation tracks the patterns of acoustic activity with a phonometer. An adaptive generative process informed by these activity patterns creates and projects carefully shaped sound events and gestures responding to the current situation as well as taking into account its development through the recent past.