Tiffany Aching’s Guide to Being a Witch is a guide to witchcraft written from the in-world perspective of Discworld character Tiffany Aching, with annotations from other characters from the Discworld novels including the witches Granny Weatherwax and Nanny Ogg.

It is notably Rhianna’s first published Discworld work; she had previously written many things behind the scenes, including a screenplay for an adaptation of The Wee Free Men completed in 2014 that remains unproduced.

[1] The book was published to celebrate twenty years of the character of Tiffany Aching, who first appeared in the 2003 Discworld novel The Wee Free Men.

[2] Like other Discworld tie-ins including Nanny Ogg's Cookbook, it is presented as though published in the fictional city of Ankh-Morpork.

It makes reference to many characters and events from throughout the Discworld novels, though primarily from the Witches and Tiffany sub-series.