Thrones, Dominations is a Lord Peter Wimsey–Harriet Vane murder mystery novel that Dorothy L. Sayers began writing but abandoned, and which remained at her death as fragments and notes. It was completed by Jill Paton Walsh and published in 1998. The title is a quotation from John Milton's Paradise Lost and refers to two categories of angel in the Christian angelic hierarchy.
Sayers had charted the developing relationship between Lord Peter Wimsey and Harriet Vane over four published novels, culminating in Busman's Honeymoon, the action of which takes place immediately following the couple's wedding. The characters appeared thereafter only in a few short stories and other published pieces, revealing only glimpses of their married life. According to Sayers' friend and biographer Barbara Reynolds, Sayers had begun work in 1936 on Thrones, Dominations, a murder mystery novel in which the Wimsey marriage was to be contrasted with those of two other couples.