Claire Tardieu is Professor of SLL at the Department of English at Sorbonne Nouvelle University. She is the author of Notions clés pour la didactique de l'anglais (2014). As a collaborator of the French Secretary of Education since 2001, she took part in several European Projects supported by the Council of Europe. She participated in writing for the Lingua D project which disseminated the tandem practice in secondary schools. Her latest studies concern teacher-to-student and peer-to-peer assessment.

Céline Horgues is a senior lecturer in the English Department, at Sorbonne Nouvelle University, where she mainly teaches English phonetics. With Sylwia Scheuer, she coordinated the collection and analysis of a multimodal corpus of English-French tandem spoken interactions (the SITAF corpus, 2012-2014), presented in the 2015 article "Why some things are better done in tandem?". In 2012, she created a tandem course and a free tandem programme for the students of her department.