Greencroft Books is a small "backwoods" publishing house based near Newport in Pembrokeshire. The business was established in 1973 by Dr Brian John, and since then he has published more than 60 titles under the Greencroft Books and Cilgwyn Publications imprints. For the most part the publications are about landscape, environment, social history, tourist guides, walking trails, geology and folklore figure prominently in the publications list. Most of the titles over the years have been written by Brian John, but he has also collaborated with a number of other authors and has commissioned others to write certain books on crafts, local history etc.

Brian undertakes most of the typesetting and design work himself, and also does much of his own photography and illustrative work. He always seeks to place his printing work with local printers so long as their prices are competitive. Book print runs are generally 2,000, and Brian does his own distribution to the West Wales trade.  Further afield, distribution is handles by the Welsh Books Council.

Greencroft Books also undertakes contract publishing, and work has been undertaken for the Pembrokeshire Coast National Park, Menter Preseli, and the Norwegian Glacier Museum.

It is a source of pride to Brian and the family that Greencroft Books has never received any grant aid from anywhere.   Unlike the majority of other publishers in Wales,  this one only publishes books that will sell in a free competitive market, that will cover their costs and turn a profit.