Stop! Is your methodology biased? Ad measurement provides 'Accountability' (to prove that ads work), however, we argue that measurement should produce 'Incrementality' (help businesses grow with ads). To measure true ad effectiveness - incrementality, we have to move away from the long-accepted methodology: pre vs. post-campaign or non-exposed vs. exposed. For this presentation we will redefine ad measurement and demonstrate how we measure it at Google with examples.