This thesis examines the ideas of social representations and the "relation to writing" (Barré-De Miniac 2000) in a multilingual context. Firstly, the thesis examines these ideas, arising from the research field of didactics of teaching French as a first language, in the multilingual context of a French program at an Australian university. Secondly, it analyses the progress in writing ability made by students from the second to the fourth year of French studies, and compares the ways in which they describe the process of writing in their first language and in a foreign language. The objective is to understand the process of writing in its psychological, social and cognitive dimensions. An analysis of the topic (Berthoud 1996) carried out on the discursive corpus of teachers (based on individual interviews) illustrates the limitations of the concept of "relation to writing" in a multilingual context, and makes it possible to identify an idea specific to this teaching situation: the "relation to the foreign language" being learned. An analysis of the topic carried out on the discursive corpus of learners (discussion groups) indicates that their written work in a foreign language originates with ideas, and that the "transposition to writing" in a foreign language can be recognised as a key point in the awareness of linguistic phenomena insofar as this as moment of writing engages knowledge of at least two languages. The situation of transition between languages, made more explicit through the process of writing, is akin to the "zone of proximal development" (ZPD) in Vygotsky's sociocultural theory in that the development of learning strategies and the internalisation of the language are apparent in this negotiation process. A comparison of the processes of writing in a foreign language and writing in a first language shows that the student's level of ability influences the attention given to different aspects of writing. The analysis of written data is divided into three parts. First, those elements in the guidelines for written assignments that reinforce literacy in the foreign language through writing are identified. Secondly, the students' written work enables exploration of another possibility in their "relation to writing". Adopting an analytical approach based on M. K. Halliday's systemic functional linguistics to determine the writer's investment in his or her output, the data show that the investment varies depending on the stage the student has reached in their foreign language learning. Finally, an analysis of the comments made by those reading or marking the work establishes a certain continuity of the topics between spoken and written discourse, and highlights the fact that these comments mainly confirm the importance of the "relation to language". The thesis contributes empirical oral and written data in a multilingual university context in which the "relation to writing" can be observed through a grasp of the continuity of the topic. It also constitutes a theoretical contribution to the teaching methodology of writing in a foreign language in that it highlights ideas including the "relation to language", the "relation to learning" and the "transposition to writing".