The Allied invasion of Sicily, codenamed Operation HUSKY, was the first combined amphibious invasion of Axis territory involving both British and U.S. forces. Poor planning and a weak operational command structure resulted in mediocre command and control of the air, land, and sea components throughout the operation. If measured by current U.S. joint doctrine, the integration of joint functions by the Allies during the Sicily Campaign was below par, leading to missed opportunities and increased costs. While Operation HUSKY still resulted in the Allied conquest of Sicily, the failures of the Allies in command and control and joint function integration during the campaign would result in greater combat losses than necessary and diminished returns during the Sicily invasion, as well as substandard operations on the Italian peninsula. The failures of integration during the HUSKY campaign illustrate why mission command and joint operations are critical components of current U.S. defense doctrine.