Privacy as a customer service. (Direct Marketing Association's Mail Preference Service,...

Last year's 20th anniversary celebration of Earth Day spurred close to 700,000 environment-conscious consumers to add their names to the New York-based Direct Marketing Association's Mail Preference Service. By opting on to the MPS list, they hope to keep their names off others.

But when one large magazine company found some of its own subscribers on that list, it decided to double-check with them. The magazine sent a letter asking them if they wanted to stop receiving all direct mail, or just what was coming from other companies. Of those who responded, most said they