In huge cities as Frankfurt (Main) a considerable part of the underground supply infrastructure is becoming continuously more and more in need of modernization. Additionally, long term planning has to consider an expected extension of supply systems. This and the consecutively necessary restructuring of the existing supply systems lead in the future to area-wide constructions within the urban area of Frankfurt. Therefore concrete possibilities for realization of accessible Multi-Utility Tunnels MUT with attractive cost saving potential due to synergy potentials are expected. Despite high launching costs, man accessible MUT represent an economical alternative due to considerably lower lifetime consequential costs. In addition man accessible MUT are environmentally preferable compared to conventional piping in form of Single-Utility Tunnels SUT respectively conventional Single-Utility Installations (SUI). The city administration of Frankfurt and the public supply company Mainova AG are cooperating on future oriented Utility Tunnel (UT) projects to cope with these challenging conditions. In this contribution the future chances and challenges as well as actual difficulties concerning technical, economical and ecological efficiency are discussed in comparison. It is much more effective to concentrate as many utilities as possible in as few tunnels as possible.