One question that often comes up when marketers are creating a campaign based on customer data is "what do we send if we don't have any data on a customer?" 

Some might default to a generic message, or not include those consumers in the mailing at all. Sephora takes a different approach. 

In this campaign, Sephora is promoting personalized product recommendations based on skin type, coloring and fragrance preferences. 

Continue reading here, I promise you you'll be amazed at how simple but clever they solved the issue of not having data for some people to personalize the message with.

Hat tip to Chat White for finding this.