This is the six-volume set, consisting of:
Vol 1, Shankara on the Absolute
Vol 2, Shankara on the Creation
Vol 3, Shankara on the Soul
Vol 4, Shankara on Rival Views
Vol 5, Shankara on Discipleship
Vol 6, Shankara on Enlightenment

The six volumes in this set are also available individually.