The paper is divided into two parts. The first part discusses the factors which will lead advertisers in general, and one advertiser specifically into complementary data sources to the traditional data banks preferred by marketers, or those preferred by the broadcast media. The goal will be to significantly improve target group identification and the evaluation and selection of media. The second part presents the information concept, "Unity of Data", from an integrated data source, which enables advertisers to identify markets and consumers in terms of media habits. A specific category will be presented to demonstrate the complete process. The presenter will also establish the close relationship of this data source to the traditional services employed by advertisers and media. It is not the intent to replace these services which best meet the demands and interests of their respective constituents. The concept of "Unity of Data" is seen as a marketing enhancement to make advertising more accountable.