In March 2015, Germanwings Flight 9525 crashed into the French Alps, killing all 150 people onboard.  An investigation found that the co-pilot deliberately steered the plane into the mountainside. It also revealed that he had a history of depression, although the airline company was unaware of this crucial information.

Worldwide, depression affects about 350 million people. Its symptoms, which differ from those of occasional sadness related to disappointment, loss, and other life changes, include persistent feelings of sadness, hopelessness, and loss of interest in work and other activities. Among workers, untreated depression can affect the ability to perform tasks and—as the Germanwings incident shows—in rare instances, can result in devastating consequences.