In 1918 the family moved to Paris, where Jules Basdevant taught public international law.

[6] She defined an international civil servant as a functionary appointed and directed by representatives of several states, or by an organization acting in their name following an inter-state agreement, who acts under special legal rules exclusively in the interests of these states.

She was a member of the Centre national de la recherche scientifique (CNRS) from 1948 to 1966 in the section of political and juridical studies.

For this reason, she was replaced at the Stresa congress on the European Coal and Steel Community in May–June 1957 by René Roblot.

[11] Bastid taught in New York and Beijing, and undertook missions in Egypt, Poland, Portugal, Uruguay, Morocco, Lebanon and Taiwan.

She sat on the administrative tribunal of the United Nations, and was a judge at the International Court of Justice in a dispute between Tunisia and Libya in 1982.