Third in the studies in Celtic coinage series the aim of this monograph is to bring together the archaeological evidence for maritime intercourse between Armorica and southern Britain in the latter part of the Iron Age. The first section ( Cunliffe ) discusses the ceramic evidence, mainly from Hengistbury Head. It suggests an intensified exchange system that probably lasted no more than sixty years (c. 120-60 BC) and served the interests of both the Armoricans and the Wessex tribes. The second section ( de Jersey ) deals with the numismatic evidence. Some 150 Armorican coins have been documented in Britain and the gold coins from Hengistbury and the surrounding area probably arrived in the context of trade during this same period. The distribution of the coins elsewhere gives indications of the extent of the trade networks. Caesar's savage reprisals following the Gaulish revolt of 56 BC disrupted these and led refugees to seek refuge in Britain; it may be that the hoard of coins found at Mount Batten resulted from some such movement. Both sections contain a useful gazetteer.