Lady Margaret Beaufort (1443-1509) was the mother of Henry Tudor (1457-1509) by her first husband, Edmund Tudor, who died before his son was born. A strong and determined woman, after many vicissitudes she was instrumental in the overthrow of Richard III and the accession of her son to the throne after the Battle of Bosworth (1485). The documents edited here are the principal household accounts, extant in St John's College, Cambridge, for the period 1498-1509, during which she ran her own household, variously at Collyweston, Croydon and Hatfield, independent of her third husband, Thomas Stanley, earl of Derby. The accounts record the economy and management of the household at the height of Lady Margaret's power, wealth, and influence and offer unique evidence of both the household and Lady Margaret herself.