Dame Kathleen Lonsdale was a pioneering woman scientist in the field of crystallography. Her discovery in 1929 that the benzene ring was flat, using X-ray diffraction methods, led to her being considered as one of the leading women in science. She was one of the first women elected as a Fellow of the Royal Society and the first female tenured professor at University College London. And in 1966, she was elected as the first woman President of the International Union of Crystallography. She appeared on Woman’s Hour in 1967 to talk about her career, about the role of science in society, and how she combined a high profile career and a family in the 1920s. This interview is part of the Woman’s Hour Collection – an archive of gems from the history of the programme. Plus Professor Dame Julia Goodfellow – Vice Chancellor of the University of Kent, following a distinguished career in science as a crystallographer, and Chair of the British Science Association – joins us to talk about her life and work, and how the position of women in science has changed since the 1920s.