Spies gather information on the sly! Discover the origin of spies, their historical development, famous spies, key skills and traits, and details about weapons, training, and assignments. Fast facts, maps, infographics, a glossary, timeline, index, and historical and color photos supplement easy-to-read text. Aligned to Common Core Standards and correlated to state standards. Checkerboard Library is an imprint of Abdo Publishing, a division of ABDO.