In the 100 years since The Defence of Duffer's Drift was first published, the face of modern warfare has changed dramatically. But what have not changed very much are the concepts of small unit tactics: Ground is held, buildings are searched, and individual enemy combatants are killed or captured by men with rifles. And those men are led by NCOs and junior officers.

The Defence of Duffer's Drift is a fictional account of a young, inexperienced British officer, who is tasked with holding a river crossing with 50 troops against a larger enemy force. His initial failures and eventual victory serve as an entertaining and instructive vehicle to convey the principles of small unit tactics.

Because it deals with principles, this definitive work has endured to this day and is still on some of the required reading lists of the U.S. Army and Marine Corps.