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.

Transgender Kendra Ferrari, 21, performs during Miss Night Queen beauty contest in Guatemala City, Friday, June 15, 2012. Ferrari won the pageant and will represent the transgender community for one year. (Photo by Rodrigo Abd/AP Photo)

Tanzania, 1964. A touching moment between primatologist and National Geographic grantee Jane Goodall and young chimpanzee Flint at Tanzania's Gombe Stream Reserve. (Photo by Hugo van Lawick via National Geographic)

Senator Barack Obama (D-IL) (R) stands in front of Senator Hillary Clinton (D-NY) as they arrive for U.S. President George W. Bush's annual State of the Union speech to a joint session of Congress at the U.S. Capitol in Washington in this January 23, 2007 file photo. Hillary Clinton announced her second run for the presidency on April 12, 2015 starting her campaign as the Democrats' best hope of fending off a crowded field of lesser-known Republican rivals and retaining the White House. (Photo by Larry Downing/Reuters)

People dancing to buskers performances in Sai Yeung Choi Street South in Mongkok district, Hong Kong, China, 28 July 2018. After 18 years of unregulated street performances, the street performers were forced to give up the space to vehicular traffic again. (Photo by Jerome Favre/EPA/EFE)

Makeup artist He Yuhong, also known as “Yuya”, checks herself in the mirror during a photo shoot following her transformation into the “Girl with a Pearl Earring”, the 17th century oil painting by Dutch painter Johannes Vermeer, at her house in Chongqing, China on August 14, 2018. (Photo by Thomas Suen/Reuters)

English singer-songwriter, dancer, model and actress Sarah Harding attends the launch of Walkers Bring It Back Campaign at Vinopolis on September 3, 2015 in London, England. (Photo by Joseph Okpako/WireImage)

An Airbus A380 aircraft prepares to land at Mumbai airport in this May 8, 2007 file photo. Sentiment at some of Asia's biggest firms deteriorated again in the fourth quarter, falling to a four-year low under the weight of concerns about slowing growth in China, the region's biggest economy, a Thomson Reuters/INSEAD survey showed. (Photo by Arko Datta/Reuters)