Faced with declining linear reach, media agencies who value TV must present the case for connected TV as a route to audience expansion. Some clients will ask whether video sharing platforms or social media are a more affordable way to achieve non-broadcast reach objectives. This presentation provides a checklist for how to prove the ROI for CTV. There is a special focus on demonstrating the impact of CTV on activation via other channels like search, display video and mobile, and the measurement and data interoperability that supports this.