LONDON (AP) — Volkswagen turns off some employees' email 30 minutes after their shifts end. Goldman Sachs is urging junior staff to take weekends off.

This surge in corporate beneficence isn't an indication that employers are becoming kinder and gentler: It's about the bottom line. After years in which the ease of instant communication via email and smartphones allowed bosses to place greater and greater demands on white-collar workers, some companies are beginning to set limits, recognizing that successful employees must be able to escape from work.

"Industry is now responding," said Cary Cooper, a professor of organizational psychology and health at Lancaster University, who says the imperative to be constantly reachable by iPhone or tablet is taking a toll on the work delivered at the office. "Employees are turning up, but they're not delivering anything."