On-the-job productivity may be increased by simply removing e-mail from the employee’s responsibilities. Gloria Mark, from the University California/Irvine (California, USA), and colleagues enrolled civilian employees at the US Army’s Natick Soldier Systems Center (Massachusetts, USA), who were hooked up to heart rate monitors, while software sensors detected how often they switched windows. People who read email changed screens twice as often (an average of 37 times per hour, versus 18 times for workers removed from e-mail), and were in a steady “high alert” state, with more constant heart rates. Those removed from e-mail for five days experienced more natural, variable heart rates, and reported feeling better able to do their jobs and stay on task, with fewer stressful and time-wasting interruptions.