Work package leader: Nils Huntemann, PTB Other participants: CMI, INRIM, LNE, OBSPARIS, NPL, VTT, BGU, LUH, UMK The aim of this work package is to improve the robustness of optical clocks and to automate their operation, with our target being to achieve unattended uptimes of 80 % – 90 % over a few weeks for both trapped ion and neutral atom lattice clocks. So far, such high uptimes have only been achieved during focused measurement campaigns, in which the optical clocks were monitored round-the-clock, with user intervention being required on a regular basis to recover failures rapidly. This approach is unsustainable over longer periods. Increasing the uptimes that can be achieved is therefore critical if multiple optical clocks around Europe are to contribute routinely to International Atomic Time (TAI) without placing unrealistic demands on their human operators. To improve the robustness of the optical clocks we will develop new approaches for automatic control and re-locking of laser systems and computer-controlled adjustment of optics. We will also develop software for automatic scheduling of procedures that currently require human intervention, such as the periodic checks that are necessary to evaluate or minimise systematic frequency shifts. Finally, we will develop tools for on-the-fly correction of systematic frequency shifts to prepare the way for real-time steering of UTC(k) timescales and contributions to TAI.