People slide down a 1,082 feet (330 metre) long inflatable water slide in Hong Kong, China August 22, 2015. (Photo by Tyrone Siu/Reuters)

A woman sits as she gets a tattoo on her leg during the annual Panama City Ink Fest in Panama City August 16, 2015. (Photo by Carlos Jasso/Reuters)

The 26th annual Visa Pour l’Image, the “Cannes Film Festival” of photojournalism kicks off, filling the French city of Perpignan with more than 3,000 of the world’s best photojournalists and photo editors, along with agencies from around the world. This year’s Visa Pour l’Image showcases 26 exhibitions around the city. Photo: Christians looting a Muslim shop in the “Combattants” district of Bangui. (Photo by Pierre Terdjman/Paris Match)

A Naga sadhu, or naked Hindu holy man, performs a ritual inside his tent during Kumbh Mela, or Pitcher festival, at Trimbakeshwar, India, Friday, August 28, 2015. Hindus believe taking a dip in the waters of a holy river during the festival will cleanse them of their sins. The festival is held four times every 12 years. (Photo by Rajanish Kakade/AP Photo)

Indian children work nearby to their parents at a construction project in front of the Jawaharlal Nehru Stadium on January 30, 2010 in New Delhi, India. The children accompany their parents to the work site, where if they are prepared to work, they will receive money for bread an milk and be provided with dinner by the contractor. The sheer scale of the project has drawn an enormous population of migrant workers from all over India.

“North and South Korea staged dueling war games Monday as threatening rhetoric from the rivals rose to the highest level since North Korea rained artillery shells on a South Korean island in 2010”. – Associated Press. Photo: North Korean soldiers with weapons attend military training in an undisclosed location in this picture released by the North’s official KCNA news agency in Pyongyang March 11, 2013. South Korea and U.S. forces are conducting large-scale military drills until the end of April, while the North is also gearing up for a massive state-wide military exercise. North Korea has accused the U.S. of using the military drills in South Korea as a launch pad for a nuclear war and has threatened to scrap the armistice with Washington that ended the 1950-53 Korean War. (Photo by KCNA/Reuters)

A pink elephant balloon, one of the entries in the Canadian Hot Air Balloon Championships, lands in a field in High River September 27, 2013. The event is a qualifier for the World Hot Air Balloon Championships in Sao Paulo in 2014. (Photo by Mike Sturk/Reuters)

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.