Originally published in 1927, this book contains the text of lectures delivered to Cambridge undergraduates between 1920 and 1926, which demonstrate the possible applications of psychological techniques to the training and deployment of soldiers. Bartlett examines features in the life of a soldier, including fatigue and the effects of battle, and offers some suggestions on how modern psychology can better be employed in the service of the army. This book will be of value to anyone with an interest in the history of psychology and the role psychology can play in the armed forces.