Unseen Hotel Workers Highlighted in New York Times

On the Road: Tipping Is Part of Travel, So What About the Maid?
By JOE SHARKEY
New York Times
BUSINESS
March 7, 2006

"Perhaps because they were unseen, hotel maids were generally overlooked by many travelers until fairly recently."

This article discusses the practice of tipping hotel maids and includes a "Travel Business Minute" video on tipping etiquette.