Christelle Avenier and Miguel Cornejo studied together at the École Supérieure de Paris Malaquais. They alternated between projects for Mathias Klotz (Santiago, Chile), Douglas Deremer Architecte (San Francisco, USA), and other French firms such as François Roche (R&Sie(n)), XTU, Jacques Ferrier, and Galiano & Simon. After being recognized in 1998 with the Robert Auzelle "Lumières de la Ville" prize, and then awarded the Electra grant (EDF) in 2000 for the city of Valparaiso, Chile, Miguel Cornejo and Christelle Avenier worked for private clients.

It was in 2007 that they began working on public projects and founded the limited liability company Avenier Cornejo Architectes. The firm then delivered a house in Orsay, ten apartments for RIVP in the 17th arrondissement of Paris, a 66-crib daycare center in the "Fréquel Fontarabie" eco-district in the 20th arrondissement for the City of Paris, and recently a young workers' residence plus a daycare center in the ZAC des Lilas development zone in the 20th arrondissement for RIVP. This last building was nominated for the 2014 Équerre d'Argent award and the 2015 Mies van der Rohe Foundation Award.

Several projects are currently under construction, including 145 apartments + a medically supervised residence + a maternal and child health center for COGEDIM and SODEARIF in the Clichy Batignolles development zone in Paris, 38 apartments for EFIDIS in Clichy-la-Garenne, and 14 apartments in the 10th arrondissement of Paris for SIEMP.