Margaret of Ypres (1216–1237) was a Flemish visionary, ascetic, Dominican penitent and flagellant. She was one of a number of 13th century lay women who led devout lives, following the example of Marie of Oignies. Called mulieres religiosae or mulieres sanctae, some gathered together in beguinages while many others lived at home practicing voluntary poverty, chastity, prayer, fasting and penance, a lifestyle known as the vita apostolica in imitation of Christ.[1] In Margaret's time, such Dominican female penitents were unregulated by the Church and were under the guidance of individual spiritual advisers. A rule would not be established until Munio of Zamora’s Rule of the Brothers and Sisters of Penance of the Blessed Dominic (Regula Fratrum et Sororum Ordinis de Paenitentiae Beati Dominici) in the late 13th century.[2]