TBF was commissioned by the city of Uster to develop the traffic engineering basis for the introduction of 30 km/h zones in the three districts of Niederuster, Riedikon and Sulzbach. For this purpose, the existing traffic and spatial situation in the residential areas was analysed and the need for traffic-calming measures was examined. As part of the process, signalization and marking plans were drawn up to document the planned modifications to the surrounding streets. The documents serve as a decision-making base for the city and support the legal implementation of 30 km/h regulations in residential areas. With our work, we contributed to the creation of low-traffic and high-quality residential areas.