Whatever his immediate background, Smith was already in command of his craft by 1749. In that year he began remodelling Governor James Hamilton's "Bush Hill" overlooking the Schuylkill and, together with Gunning Bedford, was commissioned to erect the Second Presbyterian Church at Third and Arch streets. It has been suggested that Hamilton may have recruited Smith during a trip to Britain, and certainly Hamilton was involved--at least as a donor--with several of Smith's early commissions. By 1752-1753, Smith had designed the Christ Church steeple (Second Street above Market) and both Nassau Hall and the President's House at Princeton. The latter project may have led to his being commissioned to provide plans for the College Edifice at the College of Rhode Island (now Brown University), c. 1770-1772. In fact, Smith's reputation as designer of large public buildings spread throughout the colonies. In 1770 he was responsible for the design of the new public hospital for the insane in Williamsburg, VA, and in Philadelphia he designed Carpenters' Hall--certainly a mark of esteem among his fellows of the Carpenters' Company--and the large, fireproof Walnut Street Prison (Sixth and Walnut streets), 1773-1774.

Smith was a member of the American Philosophical Society, and he assisted in erecting the platform in State House Square from which the philosophers could observe the Transit of Venus. He was also a member of the St. Andrew's Society and by the City of Philadelphia was appointed a Regulator of Party Walls and Partition Fences. Like most building trades craftsmen, Smith was warmly supportive of the Revolution. He was a member of the Committee of Correspondence from the First Continental Congress (1774), and in 1775 presented to the Committee of Safety "a model of a machine for obstructing the Navigation of the River Delaware." He freely offered his services to construct these "chavaux-de-frise" and other defences for the city. Supervising this work during the bitter winter of 1776-1777 probably contributed to his early death. The Pennsylvania Evening Post reported on 13 February 1777, "last Tuesday morning Mr. Robert Smith, architect, died at his house in Second-street, in the fifty-fifth year of his age.... Several public buildings in this city, and its environs, are ornaments of his great abilities."

The inventory of Smith's estate shows that he owned "Sundrey Books of Architecture and Drawing Instrumts" valued at nearly twenty-four pounds. Of these books we only know the titles of three: Colin Campbell, Vitruvius Brittannicus; or, the British Architect (London, 1731) purchased by Smith in 1756; Batty Langley, The City and Country Builder's Treasury of Designs (London, 1750) purchased in 1751, and Andrea Palladio, The Four Books of Andrea Palladio's Architecture (London, 1738), purchased in 1754. It is likely that Smith owned other books of architecture; he was a friend of David Hall who impored large numbers of pattern books in the 1760s, and through Hall Smith sent cash to his mother in the late 1750s and 1760s.

Smith was recognized as a leader of his profession. Owen Biddle discussed his design for the Christ Church steeple in his Young Carpenters' Assistant (Philadelphia, 1805); he featured the design in a large folding plate (perhaps based on Smith's original drawing), and wrote, "for the justness of its proportions, simplicity and symmetry of its parts is allowed by good judges to be equal if not superior in beauty to any Steeple of the spire kind, either in Europe or America." Nearly two decades after his death, the Columbianum or American Academy of Painting, Sculpture, Architecture sponsored an exhibition that included several architectural drawings by Smith, John Sproul, Abraham Colladay and Smith's son-in-law, William Williams. So far as is known this was the first exhibition of architectural drawings ever held in the United States. Unfortunately, no drawings by Smith are known to survive.

biography from Philadelphia Architects and Buildings, a project of the Athenaeum of Philadelphia. Written by Roger W. Moss.