In order to advise the determination of a planning application for a development on land at 79-81 Railway Street, Hertford, Hertfordshire, the Heritage Network was commissioned by Andrew Boakes Associates acting on behalf of Christopher Abbiss, Esq, to carry out an archaeological evaluation The excavation located the south wall of the 12th century priory church, and confirmed that medieval remains were preserved below the post-medieval demolition layers. The evaluation also showed that the impact of 19th century buildings was not as severe at previously thought and that there are likely to be medieval and earlier remains preserved across all areas of the site. On the basis of these results, the risk that the development might disturb significant archaeological remains of is considered to be High for the medieval and post-medieval periods and Moderate for all earlier periods.