Craig Lambert, a former editor of Harvard Magazine wrote about the new trend towards unpaid "shadow work" in 2011 and followed up his research in a book called Shadow Work: The Unpaid, Unseen Jobs That Fill Your Day in 2015. In it, he itemizes many of the unpaid tasks ordinary people do now that others used to do, such as pump gasoline, bag groceries, make travel arrangements, and check baggage at the airport. He includes the rise of technology and robotics as forces leading to the growth of shadow work, and also includes such factors as crowdsourcing and parental over-engagement in their childrens' lives.