Dermot Mac Cormack and Patricia McElroy are partners in 21xdesign, a design firm outside Philadelphia, USA. They met while studying visual communications in the National College of Art & Design in Dublin, Ireland in the early 1980s. Dermot was originally born in Drogheda, Ireland, and Patricia was born in Philadelphia. In 1997, they co-founded 21xdesign and have been designing and collaborating on a wide range of projects ever since. Their posters have been exhibited in the US, Poland, Ukraine, Russia, Ecuador, Ireland, and Hungary. Their posters have received numerous awards including a Platinum Award in both the 2019 Graphis Poster Annual and 2019 Graphis Design Annual. They were also invited as judges for the 2020 Graphis Poster Annual. Dermot is the department chair of the Graphic & Interactive Design Department in Tyler School of Art + Architecture, Temple University, Philadelphia.