The Inhabitant of the Lake and Less Welcome Tenants is a collection of fantasy and horror short stories by British author J. Ramsey Campbell, who dropped the initial from his name in subsequent publications.

Campbell had originally written his introduction to be included in the book The Dark Brotherhood and Other Pieces under the title "Cthulhu in Britain".

The title story introduces Campbell's fictitious book of occult lore, the Revelations of Gla'aki, similar to Lovecraft's Necronomicon.

Alas, when he sent Frank Utpatel instructions for the cover art, he misremembered the addition as and Less Welcome Tenants (perhaps with his own forthcoming Colonel Markesan and Less Pleasant Persons in mind).

After many nightmares and visions of the images in the water, he eventually becomes insane and ultimately jumps into the pool with his female companion.