 Early in Joseph Potter's career as an architect, he was employed by James Wyatt (a prominent architect at the time) to supervise the alterations to Lichfield Cathedral in 1788–93 and Hereford Cathedral in 1790–93.In this period he also worked under Wyatt in the repair to St Michael's Church, Coventry (now St Michael's Cathedral) in 1794 and the rebuilding of Plas Newydd, Anglesey for the 1st Marquess of Anglesey.At Plas Newydd it is thought Potter is solely responsible for the design and build of the gothic chapel.