This presentation provides an overview how CQ was implemented at ESO. It reviews the approaches and concepts that were chosen, making sure that all operational and authors’ requirements were satisfied, and how it was achieved to have an implementation and rollout of CQ5 in only three months. Also, the presentation will provide an overview of the architecture of the Day CQ system at ESO and its marriage with pre-CQ system. Rein Warmels, Astronomer & Christina Garcia de Juan, Management Consultant, European Southern Observatory