This paper explores how the influence of cybernetics within structuralism contributed to Lacan’s theory of the signifier as (functioning within a) structure. By examining his Freudian exploration within the broader scheme of American and French thought, the author extrapolates the link between these two theoretical paradigms and the implications that this had for his work. It is argued that in contrast to the apparent ease with which the structuralist paradigm was incorporated into Lacan’s theory, the surprise of his Seminar attendees when presented with cybernetics in 1954 was not altogether warranted. By exploring the close interaction between Jakobson and Lévi-Strauss during the 1940s, the author shows that the structuralist paradigm was already quite heavily invested by cybernetics. In commenting on two slightly different translations of an intervention that Lacan makes during the Bonneval Colloquium with Jean Hyppolite, the author pinpoints a likely turning point within Lacan’s work, within the context of his thesis on the temporality of the signifier and its relationship to the Freudian notion of repetition.