As yet, a good German translation does not exist of this pivotal work, nor is an introduction available whichexplains the central topics in a comprehensible yet authoritative manner. This gap is filled by the present work which uses key themes from Thomasian philosophy (and theology) to provide an introduction to the overall conception of the Summa theologiae. The review of the present state of research on the Summa theologiae provides a comprehensive handbook particularly suited for university teaching. It is designed not only for the specialist reader but equally for those with a general interest in the subject.