In this segment of Secrets of Selfridges, learn how Selfridge's groundbreaking innovations such as the first-floor cosmetic department have inspired modern retail psychology. Due to Edwardian trends of the time, his competitors usually hid makeup away on higher floors, but Selfridge challenged the notion of the time by placing everything together at the front of the store. His novel idea has now become the template for department stores around the world. When WWI began in 1914, some department stores turned the war to their advantage. Selfridges posted record annual profits by the end of the war allowing him to add an extension to the store just in time for the economic boom of the 1920s.