This chapter explores how Kant's philosophy connects with the spirit and the systematic interest of the Leibniz-Wolffian philosophy. Sánchez-Rodríguez then shows how this tradition undergoes a critical transformation at the same time, mainly due to Kant's rejection of its metaphysical foundations. Specifically, the chapter explains how Leibniz's system of pre-established harmony theory is adopted and transformed in Kant's critical theory of reflective judgment and teleology.