Studied Egyptology at the Universities of Leiden, Copenhagen, Oxford and Amsterdam. Assistant curator at the Museum of Antiquities, Leiden from 1958-1962. Afterwards worked as a publisher for many years. Lecturer at Leiden University since 1984, specializing in the hieratic script and in the socio-economic history of the New Kingdom, notably of the inhabitants of Deir el-Medina. Currently working on the publication of hieratic papyri in Turin, ostraca in London, Cairo, Brussels and several other collections, and graffiti from several sites in Egypt, such as Thebes, Saqqara, Edfu, Hierakonpolis and Deir Abu Hinnes.