This study is an historical analysis of the Soviet operational use of tank and mechanized corps, and tank armies, in the deliberate defense at the Battle of Kursk in 1943. It centers on the question of how effective was the Red Army in employing these units during this momentous battle. Events that shaped the battle and a brief comparison of forces set the stage. A discussion of the actual battle on the Central and Voronezh Fronts is followed by an analysis of the effectiveness of the employment of the operational armored units.The battle analysis methodology as promulgated by the Combat Studies Institute at the United States Army Command and General Staff College, Fort Leavenworth, Kansas, established the guidelines for the study. Both Western and Soviet sources were utilized. Objectivity and compatibility of all available source material were of paramount importance in establishing the validity and accuracy of various accounts.The study concludes the Soviets prepared superbly for the operational battle; however, execution fell short of expectations. Because this was the first time the Soviets used tank armies in battle, an analysis of Kursk serves as an excellent catalyst for subsequent examination of present Soviet defensive doctrine and the use of tank armies in defense.