In this chapter and the next an attempt is made to offer a geographical and chronological framework which will allow the regional differences between the Iron Age communities of Britain to be described in a manner as objective as possible. There are several potential approaches which could have been adopted - pseudo-historical, chronological or cultural. All present difficulties. A pseudo-historical model couched in terms of invasion and folk movement would have imposed a prejudged structure upon the evidence; a purely chronological system lacks sufficient absolute dates for calibration and would, in any event, take no account of spheres of contact or different rates of development; while a cultural model, in the style laid down by Childe, is extremely difficult to apply to the British material and is of very doubtful value in characterizing a territory in which the communities are in close contact and share many systems in common. Accordingly, these conventional schemes have been rejected.