Since 1989 he has worked closely with Freda Sack on a broad range of type projects. In 1990 they co-founded The Foundry, to design, manufacture and market their own exclusive typefaces designed by the partners to designers and businesses internationally. The Foundry also developed custom typefaces, marks and logotypes for companies internationally those included: a special typeface to be readable at very small sizes for Yellow pages, corporate fonts for BG plc (British Gas) NatWest Bank and signage typefaces for both RailTrack in the UK and the Lisbon Metro system in Portugal. Yellow Pages typeface received a D&AD Silver Award.
In 1978 along with Sue Cavendish and a dedicated handful of passionate designers and craftsman from all the lettering arts he founded Letter Exchange. He was its chairman for many years. Twenty-five years later it is still a thriving society.
He was elected a Fellow of the International Society of Typographic Designers (ISTD) in 1992 and was joint chair of the ISTD from 1994–99. He is involved as an accessor on the ISTD yearly student assessment scheme and was on twice on the panel of international judges of the ISTD TypoGraphic Awards 92.
David Quay lectures extensively in typography and type design both in the UK and internationally. He has had a long association with the London School of Printing and has been a visiting lecturer at the Danmarks Designskole in Copenhagen, Hochschule für Gestaltung Offenbach and for three years Professor of typography and book design at the Fachhochschule Mainz. In 2000 he moved to Wiesbaden and in 2001 to Amsterdam. In Holland he taught typography and design at Akademie voor Kunst en Vormgeving|St. Joost, Avans Hogeschool Breda.
David Quay now works as an independent type designer and graphic designer for clients internationally and designs new typefaces for The Foundry in London. He lives and works happily from his studio in Amsterdam.