Around the world, highly skilled dog teams keep us safe, detecting explosives and contraband. But how did humans and canines team up in the first place? That is a fascinating, heartbreaking and largely unknown story dating back to the Civil War when dogs tagged along as battle mascots. Soon they showed their usefulness in an amazing number of tasks taught to them by the humans with whom they bonded. The military was slow to appreciate the value of K-9 teams, but over time the dogs'devoted handlers won respect and important rights for their four- footed comrades.