In this first volume of a planned two-volume set, Zamulin takes a close look at the condition of the German and Soviet forces following the winter campaign. Analysing first the German side, the author demonstrates that the Germans were in a woeful condition, especially with respect to the number of serviceable armored vehicles and the lack of infantry. However, Hitler was determined to regain the initiative in the East, though some German commanders expressed concerns. Zamulin then looks at the German plans for the summer of 1943 and the process of rebuilding its forces. As he shows through data, the Germans struggled to replenish Army Group South and Model's Ninth Army in the north, and the latter was hampered almost right up to the launching of Operation Citadel by the need to conduct a major anti-partisan operation in the woods and thickets in the German rear, using panzer and infantry divisions that had been earmarked for Citadel. Zamulin next examines the Soviet side, and discusses the planning for the summer campaign, including the decision to adopt a pre-meditated defense of the Kursk salient and to create a multi-echeloned system of defense (though incomplete in depth). The author demonstrates that the Red Army was able quickly to replenish its forces and also create a large mobile reserve, the Steppe Front. Thus, the delay in launching Citadel was not the fatal German error, and it would have failed even if launched earlier. 114 photographs, 39 tables