Baret and Commerson joined the Bougainville expedition at the port of Rochefort in late December 1766. They were assigned to sail on the storeship, the "Étoile". Because of the vast quantity of equipment Commerson was bringing on the voyage, the ship's captain, François Chenard de la Giraudais, gave up his own large cabin on the ship to Commerson and his "assistant". This gave Baret significantly more privacy than she would have had otherwise on board the crowded ship. In particular, the captain's cabin gave Baret access to private toilet facilities so that she did not have to use the shared head with other members of the crew.