Between the 28th of April and 23rd July, Oxford Archaeology East undertook an archaeological excavation at land south of Dereham Road, Mattishall (TG03951118). A total of 1.2ha was excavated in advance of residential development. The excavation revealed three main phases of activity spanning the medieval through to the post-medieval periods, with a focus being on the development of a common edge settlement established between the 12th-14th centuries. In addition to the (reworked) boundary demarcating the southern edge of Mattishall's West Green common, the fieldwork uncovered evidence of numerous related plots, boundary ditches and other features, including an area of pits associated with a probable smithy or forge. A clear shift in the nature and intensity of activity was evident in the late medieval period (14th-15th centuries), while during the post-medieval period (16th-19th centuries) the focus moved to the east of the site, closer to Mattishall village, where the remains of a structure depicted on 19th century maps were revealed. The excavations produced a fairly typical finds assemblage, including a moderately-sized group of medieval to post-medieval pottery, alongside lava quern stone, ceramic building material and (structural) iron objects. More unusual is the significant quantity of metalworking waste recovered from an area in the eastern part of the site. Botanical remains were sparse and poorly preserved, but appear consistent with comparable sites in the region, while the modestly-sized faunal assemblage suggests a predominantly pastoral economy based largely on cattle and sheep/goat. Together, the stratigraphic, ecofactual and artefactual remains have good potential to contribute to wider research into the origins, development, economy and eventual decline of common-edge settlements in Norfolk and beyond.