Two phases of archaeological excavations were undertaken within the Tilly's Lane development area on the north side of Staines High Street. A single trench was excavated at Tilly's Lane East between April and June 1999, with two trenches at Tilly's Lane West - British Gas and High Street sites - between February and May 2000. All the trenches lay on the gravel island, though Tilly's Lane East and the British Gas site lay within early flood zones. Limited evidence of Bronze Age activity was observed in the western trenches, including flood defence measures and probable agricultural activity. The major phase of activity was in the early Romano-British period, where domestic - including an in situ tessellated floor surface and associated wall lines indicative of a substan\ial structure - and small-scale industrial activity was concentrated in the area of the central, 'dry' High Street site. Activity of a more marginal character was occurring to the west, with the disposal of domestic debris and burial of neonatal infants. Flooding was clearly still a problem at this time, with broad ditches forming flood defences and evidence for at least one major alluvial incursion. The late Romano-British period saw a shift in occupation to either end of the island, presumably concentrated around the crossing points to the east and west. Most of the evidence from this phase is suggestive ofagricultural activity, possibly of high value crops on the west side. Medieval activity of 11-14" century date was concentrated in the east, where ditches on the same alignment as the north-south burgage ditches and backland boundary plots observed in the previous excavations at CTE Staines, suggest a similar land use. Evidence from the west end ofthe island was for disposal of domestic refuse, whilst there was negligible evidence from the High Street site, again suggesting a shifting emphasis in land use