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Evidence for relative sea-level changes during the middle and late Holocene is examined from two locations on the Atlantic coast of Harris, Outer Hebrides, Scotland, using morphological mapping and survey, stratigraphical, grain size and diatom analysis, and radiocarbon dating. The earliest event identified is a marine flood, which occurred after 7982-8348 cal. a (7370 AE 80 14 C a) BP, when the sea crossed a threshold lying at À0.08 m Ordnance Datum Newlyn (OD) (À2.17 m mean high water springs (MHWS)) before withdrawing. This could have been due to a storm or to the Holocene Storegga Slide tsunami. By 6407-6122 cal. a (5500 AE 60 14 C a) BP, relative sea levels had begun to fall from a sandflat surface with an indicated MHWS level of between 0.08 and À1.96 m (À2.01 to À4.05 m). This fall reached between À0.30 and À2.35 m (À2.39 to À4.44 m) after 5841-5050 cal. a (4760 AE 130 14 C a) BP, but was succeeded by a relative sea-level rise which reached between 0.54 and À1.57 m (À1.55 to À3.66 m) by 5450-4861 cal. a (4500 AE 100 14 C a) BP. This rise continued, possibly with an interruption, until a second sandflat surface was reached between 2.34 and À0.26 m (0.25 to À2.35 m) between 2952-3375 cal. a (3000 AE 80 14 C a) and 1948-2325 cal. a (2130 AE 70 14 C a) BP, before present levels were reached. The regressive episode from the earliest sandflat is correlated with the abandonment of the Main Postglacial Shoreline. It is maintained that the fluctuations in relative sea level recorded can be correlated with similar events elsewhere on the periphery of the glacio-isostatic centre and may therefore reflect secular changes in nearshore sea surface levels. Despite published evidence from trim lines of differential ice sheet loading across the area, no evidence of variations in uplift between the locations concerned could be found.