Index Architekten was established in Frankfurt-Main by Sigrun Musa and Ulrich Exner in 1990.

Whether dealing with urban design, architectural design or an interior task Index Architekten always emphasize atmosphere and sensuality. For the architects it is also about designing spaces, which have essential vibrations and touch the human being.

The architects are motivated by the haptic and sound quality of a material, the atmosphere created by colour or the memory that is evoked through a certain room sequence. These things lying on the brink of predictability are as important to the Architects as the pragmatic and technical solution of a design or construction process.