American pop star Nicole Scherzinger, 43, of NBC's Annie Live! and FOX's The Masked Singer visits The Empire State Building on November 12, 2021 in New York City. (Photo by Roy Rochlin/Getty Images for Empire State Realty Trust)

A woman films with her phone the incineration of packages of cocaine, part of a high seas drug seizure of 135 bundles by Salvadoran Naval Force, at a police base in Ilopango, El Salvador, November 29, 2021. (Photo by Jessica Orellana/Reuters)

English actress Michelle Keegan at “The Jonathan Ross Show” TV show, Series 18, Episode 7 in London, United Kingdom on December 4, 2021. (Photo by Brian J. Ritchie/Hotsauce/Rex Features/Shutterstock)

Selena Gomez attends the 2019 American Music Awards at Microsoft Theater on November 24, 2019 in Los Angeles, California. (Photo by John Shearer/Getty Images for dcp)

A model presents a creation by German designer Karl Lagerfeld as part of his Haute Couture Fall Winter 2015/2016 fashion show for French fashion house Chanel at the Grand Palais which is transformed into a casino in Paris, France, July 7, 2015. (Photo by Stephane Mahe/Reuters)

The selfie is the most popular photography trend of the internet today. It's gotten so popular, in fact, that even our beloved feline friends have started to catch on. I dare you to keep the smile off your face for this one!

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.