Maria Goodavage's new book "Soldier Dogs: The Untold Story of America's Canine Heroes" takes a look at the remarkable bond between military dogs and their handlers. We're sharing 15 of our favorite photos from her book; each captures this extraordinary relationship.

Handlers Leave No Dog Behind

Handlers Leave No Dog Behind

Military code requires that injured comrades not be left behind in a combat zone — and that includes soldier dogs. On a 114-degree day, Sgt. Adam Miller carries his dog, Tina M111, to safety after she was “shot” during an Inter-Service Advanced Skills K-9 (IASK) training course. (Tina was not actually harmed during the drill.)

A Long History of Canine Heroes

A Long History of Canine Heroes

This photo from World War II’s Battle of Peleliu is a favorite of Vietnam vet and dog handler Robert Kollar. To him, the image of Marine Cpl. William Scott, and his Doberman Pinscher, Prince, captures everything about the bond between wartime handler and dog.

Off-Leash Training Leads to Life Saving

Off-Leash Training Leads to Life Saving

Off-leash training allows dogs to follow their noses while searching for explosives. At the same time, having the dog off leash helps to keep his handler out of harm's way. Navy Master at Arms 2nd Class Joshua Raymond and his dog, Rex P233, learn to work off leash together for the first time at a Yuma, Ariz., predeployment course.

Even Working Dogs Need To Practice Good Dental Care

Even Working Dogs Need To Practice Good Dental Care

Serving in a combat zone doesn't mean neglecting basic health issues — for soldiers or their dogs. Air Force Staff Sgt. James Bailey gives Ajax L523's teeth a good brushing while on deployment. Smile, Ajax!

Small Dogs Can Be Soldier Dogs, Too

Small Dogs Can Be Soldier Dogs, Too

Who says you have to be a big dog to be a soldier dog? Lars J274, a Jack Russell Terrier, is the perfect size for sniffing out bombs in submarines. Other breeds that do well as military dogs are German Shepherds, Belgian Malinois and Labrador Retrievers (for sniffing).

Don't Judge a Dog By Its Name

Don't Judge a Dog By Its Name

Despite the name, Davy N9532 is a female dog. It is not uncommon for military working dogs to have names that do not match their gender. These dogs can also have goofy names that don't quite match their stature, such as Baby Cakes, Busty and Moo. The breeder, often from Europe, assigns the moniker.

A Careful Nose Detects Danger

A Careful Nose Detects Danger

Soldier dogs and their handlers frequently work as a team. In this case, little Lars’ handler lifts him from bunk to bunk on the USS Norfolk so his nose can get close enough to detect explosives on any level.

Under-Recognized Heroes

Under-Recognized Heroes

These four-legged heroes play a crucial role in the military but often don't receive formal recognition for their efforts. Air Force Staff Sgt. Brent Olson was awarded a Purple Heart for his actions in Afghanistan. His soldier dog, Blek, who was injured at the same time, received no official honors. (Although we expect there was much unofficial appreciation.)

Bonding During Some Downtime

Bonding During Some Downtime

While many soldier dogs risk their lives in combat situations, others do the important work of teaching human soldiers to be handlers. "Training aide" dogs are not active military working dogs; they are used for training exercises only. Here, a training aide dog and his handler-in-training start the day enjoying the shade at the Department of Defense Military Working Dog School at Lackland Air Force Base in San Antonio, Texas.

Guard Dog Takes Loyalty to a New Level

Guard Dog Takes Loyalty to a New Level

Lex L479 and his handler would often spend the night in the foxholes they shared while on patrol in Afghanistan. But there was no rest for Lex; once his handler fell asleep, the Belgian Malinois would crawl out from their tarp-protected foxhole and stand guard over him through the night — often in torrential rains.

"I Trust Her With My Life"

"I Trust Her With My Life"

Soldier dogs and their handlers have an amazing bond that goes beyond simply training together. Army Staff Sgt. Marcus Bates, seen here enjoying a little downtime with Davy, says, “I trust her with my life. If I didn’t trust her, I wouldn’t be here.”

A 24/7 Bond

A 24/7 Bond

Dogs on deployment often share their handlers’ bunks and even sleeping bags. Being together nearly 24/7 deepens the already incredibly tight bond between dog and handler. Pictured here, Air Force Staff Sgt. Christine Campos relaxes on her cot with her dog, Bico F544.

Not All Dogs Can Be Military Dogs

Not All Dogs Can Be Military Dogs

Soldier dog Rex — seen here standing guard in Iraq as his soldiers take a lunch break in their Stryker vehicle — did not make it as a patrol dog because he was too gentle. “If you were playing and you acted as if he bit you, he'd let go and look all sad,” Army Sgt. Amanda Ingraham says. But she knew he would put his life on the line to protect her. And that's just what Rex does; instead of working patrol, his job is to sniff out IEDs (improvised explosive devices).

Soldier Dogs Require Special Gear

Soldier Dogs Require Special Gear

War hero Fenji needs to wear “Doggles” to help with an eye problem, but she doesn’t much care for them. When she’s not working, she tries to take them off at every opportunity.

The Heartbreaking Reality of War

The Heartbreaking Reality of War

The biggest danger soldier dogs and their handlers face in combat is stepping on or accidentally triggering an IED while trying to locate or disarm them. The Marine dog handlers pictured here mourn the loss of a beloved fellow handler.