The Dove Nutrium Bar Cross-Media Case Study represents a breakthrough in marketing mix measurement; it answers the question of where Online fits into the marketing mix. In answering this question, the case study applies a combination of best practice research techniques, which this paper will review. The study, led by Rex Briggs in partnership with Unilever, MSN, the ARF, the IAB and supported by Dynamic Logic research technology provides a real-world, side-by-side, dollar-for-dollar comparison of Television, Magazine, Radio, and Online effectiveness. The methodology has now been replicated and refined for six additional marketers. The findings shed new light onto the complementary nature of Online and Offline advertising and reinforce the idea of “surround sound marketing.” However, the purpose of this paper is not to review the findings. Rather, the purpose of this paper is to examine the use of best industry practice to develop this break-through research approach. This paper begins with the history and challenges of cross-media measurement and then dissects the groundbreaking methodology and analysis used to overcome these challenges.