Ever since Google announced the end of third-party cookies several years ago, marketers have been working to find ways to engage customers and meet marketing goals without cookies. Although a lot of first-party data is available via social media and walled gardens such as Amazon, Meta and Google, it has gotten more difficult to obtain because of price increases and consumers blocking app tracking. 
So, what are marketers turning to as an alternative data source? Email.
Email may seem old-school, but it is the most personal and engaged channel. One study found that over half (57%) of Gen Z consumers prefer email contact from brands over any other channel. Because they have opted in to an email subscription, consumers want to read the content and engage, including the ads.
Data derived from email campaigns is core to other channels. Email is also a basis for building lookalike audiences and efficient strategies for acquisition.