The next part of the law of things is the law of succession, which governs what happens to a person's property and obligations when that person dies.

The Roman law of succession has some important fundamental differences from the Scots law, and much of the Roman influence that there was has been superseded by modern legislation. However, as we shall see as we go along, there are some points of continuing Roman influence.

Part Four consists of a single chapter, namely Chapter 16. This chapter begins by considering some general concepts in the law of succession. It then considers in turn the cases of intestate succession (i.e. where there is no will) and testate succession (i.e. where there is a will).