In February 1760, Robert Mylne (1733–1811) was declared the winner of the competition for the design of a new bridge to be erected at Blackfriars, London. Work on the foundations began immediately. There were delays in the building programme, certainly, but they were not serious and there were good reasons for them. The bridge was fully opened to traffic in November 1769, and was widely admired, both for the aesthetic of its appearance and its commercial success and general usefulness (Fig. 1). Why then should it have taken over six years, until March 1776, to settle the architect’s bill? This article explores possible answers to the question by considering what parts of the project might have gone wrong, or what other reason would explain the City’s prevarication.