The next generation of (access) regulation addresses the regulatory issues arising from the modernization of telecommunications networks through the rollout of fiber optics. Although the current investments are fundamentally made under the conditions of liberalized markets, sector-specific regulation according to the Telecommunications Act (TKG), which significantly exceeds the objectives of general antitrust law, remains essential for effective competition in the telecommunications sector. In addition to the general principles of sector-specific regulation derived from Union and constitutional law, the implications of the modernization process for regulation are specifically outlined, and concrete options for action by the Federal Network Agency are analyzed.