MarketingSherpa has a case study up today about a company that took an aggressive stance on re-engagement that reduced their house list size by over 95%. While the size of the list went down, online sales doubled.

The whole article is a lesson in how to do email right. They are sending relevant and engaging mail to their subscribers. They kept the addresses of people who wanted the mail, but designed a new program from the ground up. All of the key points I, and others, keep talking about is present in their new program.

• they had a defined content strategy
• they had permission to send
• they sent consistently
• they sent engaging emails
• they maintained their lists aggressively

In short, they provided a valuable set of emails that their recipients wanted effectively. And with a list 25% of the size of the unengaged list they started with, they have doubled online sales.