Lloyd Williams and Underwood was a firm of architects based in Denbigh and active mostly in North Wales in the second half of the 19th century.
The partners were Richard Lloyd Williams, formerly a pupil of Thomas Fulljames, and Martin Underwood, who was also county surveyor for Denbighshire.
Several of their designed now have listed status.
[1] The firm's designs include: Lloyd Williams and Underwood published some self-authored books in 1872, titled Architectural Monuments of Denbighshire and Village Churches of Denbighshire.