For many, man's best friend is more than just a pet. As Russian photographer Yuri Ivashchenko came to discover, some of the most invaluable to society are the German and Belgian Shepherds trained for detecting explosives. In 2014 Ivashenko visited two hydroelectic power plants situated on the Sulak river in the republic of Dagestan in southern Russia, where he photographed the sniffer dogs and their trainers. “In this line of work, as the main dog expert on the ground told me, the dog is a tool. They have a demanding job. Their main responsibilities include inspection of the plants, the surrounding area, tunnels as well as any arriving vehicles,” Ivashchenko says. For the humans, the work is no less hazardous. “The trainer must be alert at all times and be sensitive to the dog’s behaviour,” explains the photographer. Their dedication left an impression on Ivashenko, teaching him to be prepared for the unexpected as a photographer. “One unforeseen incident involved a pregnant German shepherd that had escaped from its cage and bit me, not very deep,” Ivashchenko says. An “initiation” in the photographer's words, or a “test of mutual trust”, according to the dog's handler.