Abstract In May 1919 the first female Fellows of the Geological Society were elected and from then on attended meetings at the Society. The first person on the female fellows’ list was Margaret Chorley Crosfield. She was born in 1859 and died in 1952. She lived all her life in Reigate in Surrey. After studying and then leaving Cambridge, Margaret had sought to join the Geological Society of London for many years, in order to gain recognition of her research work, but also to attend meetings and use the library. This paper will look at her history and trace her geological achievements in both stratigraphy and palaeontology, as well as her extraordinary field notebooks that she left to the Geological Survey. She worked closely with two female geological colleagues, Mary Johnston and Ethel Skeat. Margaret Crosfield epitomizes the educated, amateur, independent woman who wanted to be recognized for her work, especially fieldwork, at a time when female contributions, especially in the field sciences, were not always acknowledged or even appreciated.