Like many other postmodern novels, Fowles uses multiple different stylistic and structural techniques to highlight his thematic interests in The French Lieutenant's Woman. When discussing these stylistic concerns, many literary critics comment on the importance of the narrator and the narration, the intertextual references to other literary works, and the multiple endings.
Throughout the novel, the omniscient narrative voice alongside a series of footnotes seem to objectively reflect on his difficulties of controlling the characters, the conventions that are expected of a "Victorian novel" and analyses of differences in 19th-century customs and class. The narrator often returns to discussions of high importance in the literature and scholarship of the period, like the theories of Charles Darwin, the radical politics of Karl Marx, and the works of Matthew Arnold, Alfred, Lord Tennyson, and Thomas Hardy. Through this metafictional and metahistorical voice, the clearly contemporary postmodern narrator questions the role of the author and the historian in thinking about the past. In her article discussing the use of paratext, or the contextualizing text printed in the book such as the footnotes and epigraphs, Deborah Bowen argues that the novel's paratext forces the reader, like in other postmodern works, to rethink the importance of such peripheral material that in other contexts will get overlooked in light of preference for the main text. Instead of nicely complementing the main plot and adding meaning, these paratextual elements do not always contribute to the effectiveness of the novel and often act to unseat the authority of the narrative voice.
Beyond the prominent narratororial intervention emphasizing particular interpretations of the text, the book's metafictional approach often relies on intertextual references to provide further commentary. In the epigraphs for each chapter, the book gestures towards a number of important 19th-century texts and ideas. Partially, references to other texts act in "ironic play", parodied by how the novel emulates other Victorian conventions throughout the text. Linda Hutcheons describes the works of William Thackery, George Eliot, Charles Dickens, Froude and Thomas Hardy as direct inspirations for this parody. In his discussion of science and religion in the novel, John Glendening notes that both character commentary on Darwin's publications along with the epigraphs mentioning those works as direct contributor's to the novels emphasis on science superseding religion. Similarly, by quoting Marx with the first epigraph, along with multiple subsequent epigraphs, thematically the novel directs attention towards the socio-economic situations created within the novel. Deborah Bowen notes the trend in literary critics struggle to find reading of the epigraphs that help understand the themes of the novel, and argues that the poor synchronicity of epigraphs with text "disperses the authority of the narrative voice, thus destroying his power to speak as a moralist." For Bowen, the epigraphs support the satire of Victorian fiction conventions in the novel.
Often critics will comment on the novel's multiple endings. Each offers a possible ending for Charles's pursuit of Sarah: the first ends with Charles married to Ernestina, the second with a successful reestablishment of a relationship with Sarah, and the third with Charles cast back into the world without a partner. Michelle Phillips Buchberger discusses these endings as a demonstration of "Fowles's rejection of a narrow mimesis" of reality; rather Fowles presents this multiplicity of endings to highlight the role of the author in plot choices.