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Abstract. Widespread existing geological records from above the modern ice sheet surface and outboard of the current ice margin show that the Antarctic IceSheet (AIS) was much more extensive at the Last Glacial Maximum (∼ 20 ka) than at present. However, whether it was ever smaller thanpresent during the last few millennia, and (if so) by how much, is known only for a few locations because direct evidence lies within or beneath theice sheet, which is challenging to access. Here, we describe how retreat and readvance (henceforth “readvance”) of AIS grounding lines during theHolocene could be detected and quantified using subglacial bedrock, subglacial sediments, marine sediment cores, relative sea-level (RSL) records,geodetic observations, radar data, and ice cores. Of these, only subglacial bedrock and subglacial sediments can provide direct evidence forreadvance. Marine archives are of limited utility because readvance commonly covers evidence of earlier retreat. Nevertheless, stratigraphictransitions documenting change in environment may provide support for direct evidence from subglacial records, as can the presence of transgressionsin RSL records, and isostatic subsidence. With independent age control, ice structure revealed by radar can be used to infer past changes in iceflow and geometry, and therefore potential readvance. Since ice cores capture changes in surface mass balance, elevation, and atmosphericand oceanic circulation that are known to drive grounding line migration, they also have potential for identifying readvance. A multidisciplinaryapproach is likely to provide the strongest evidence for or against a smaller-than-present AIS in the Holocene.