The purpose of this essay is to illuminate the functions of the concepts Free Will and Convention in The French Lieutenant’s Woman. By examining the three main characters, Sir Charles Smithson, Sarah Woodruff and Ernestina Freeman and the relationships between them, one is made aware of the impact and subtlety of free will and convention on the development of their lives. In this essay I demonstrate how Fowles reveals his thoughts on free will from three different perspectives: social, existential, and narrative. He develops a social perspective by placing his characters in a Victorian setting, while letting them be analyzed and criticized by a post-modern narrator. The reoccurring themes of fossils and the theory of evolution represent a good part of his existential perspective. By writing in the genre, Metafiction, Fowles asserts his free will by shifting the characters and the reader back and forth between the nineteenth and twentieth century and experimenting with the two final endings. I conclude that Fowles’ message to the reader is that free will constitutes a strategy of survival and a way of enriching one’s life.