A report on rescue excavations that took place from 1989 to 1991 in advance of the new A27 Brighton bypass. The project involved the investigation of known sites and the recovery of palaeoenvironmental data, although it also recorded two new Middle Bronze Age sites, Mile Oak Farm and Downsview. This detailed report brings together the work of this project with existing information resulting in a synthesis of developments on the South Downs during the Middle to Late Bronze Age and through to the Early Iron Age.