In this doctoral project, we propose to address the many challenges that are found on the way to the development of advanced cost-effective telecom network integrated CV-QKD systems that are ready to operate in a deployed optical fibre environment. These include the conception and implementation of solutions for a system operation in the so-called local Local Oscillator configuration, with suitable modulation schemes (and associated security proofs), as well as with adapted high-speed electronics. The thesis work will also include the characterization of photonic integrated CV-QKD transmitter and receiver chips on both the silicon and indium phosphide platforms, and their use for secret key generation. This will be crucial for future scalable solutions for QKD systems.