Bartrum joined the British Museum's Department of Prints and Drawings in 1979. She became Curator of German prints and drawings in 1991. In the latter role she was also responsible for coordinating between departments, research into the
provenance history of items held in the British Museum collections which may relate to the
Nazi era. Bartrum's first book was
German renaissance prints 1490–1550, which was the catalogue of an exhibition held at the museum during 1995. Bartrum is an authority on the art of
Albrecht Dürer and her catalogue for the 2002-03 exhibition
Albrecht Dürer and his Legacy, published jointly by the British Museum Press and
Princeton University Press in 2002, won the 2003
Art Newspaper/AXA Exhibition Catalogue of the Year Prize. She edited a work on Edward Munch's prints in to accompany a 2019 exhibition
Edvard Munch: love and angst, published by Thames & Hudson in collaboration with the British Museum. Bartrum retired from the British Museum in November 2019. ==Selected publications==