Models Miranda Kerr, Candice Swanepoel, Adriana Lima and Erin Heatherton attend The Reveal of the What Is s*xy? List celebrated by Victoria's Secret Bombshells at The Beverly on May 12, 2011 in Los Angeles, California. (Photo by Charley Gallay/Getty Images for Victoria's Secret)

A member of the Eton public school O.T.C. (Officers Training Corps) practising shouting out orders during a training session, 20th January 1940. (Photo by Hulton Archive/Getty Images)

A Shi'ite worshiper bleeds after cutting his scalp in a ritual display of mourning during an Ashura commemoration ceremony outside Kadhimiya shrine on December 6, 2011 in Baghdad, Iraq. Ashura marks the death of Prophet Muhammad's grandson the revered Imam Hussein in Karbala, Iraq in 680 AD. Shi'ite festivals were prohibited during the time of Sunni dictator Saddam Hussein's rule. (Photo by Mario Tama/Getty Images)

An old woman smokes a cigar at Old Havana's Plaza de la Catedral on February 07, 2006 in Havana, Cuba. (Photo by Marco Prosch/Getty Images)

Jenifer Lopez, 12, watches television at her home in Havana January 9, 2015. (Photo by Alexandre Meneghini/Reuters)

Buyan, a male Siberian brown bear, is given a shower by a zoo employee in his enclosure at the Royev Ruchey zoo in Russia's Siberian city of Krasnoyarsk June 24, 2014. The Siberian city has been experiencing temperatures of around 30 degrees Celsius over the last week. (Photo by Ilya Naymushin/Reuters)

Students exercise in body training at Bishan Vocational Education Center in Chongqing, southwest China, January 13, 2016. These students were trained to be stewardesses of the high-speed train. (Photo by Xie Jie/Xinhua)

Throughout the course of the long war in Afghanistan, Coalition troops have relied on thousands of military working dogs to help keep them safe, and make their jobs easier. The dogs are trained to detect explosives, to find illegal drugs, to search for missing comrades, or target enemy combatants. Not only are they active on the front lines, but behind the lines they serve as therapy dogs, service dogs, and loyal companions. They also share the same risks as the ground troops, suffering injuries and sometimes death on the battlefields. Gathered here are images of these dogs and their handlers in Afghanistan and back home, from over the past several years, part of the ongoing series here on Afghanistan.