Callista was admitted as a lawyer in 2012 and called to the Bar in 2023.

She accepts briefs in all areas of commercial and public law. She has particular expertise in matters involving issues of private international law, international arbitration and public international law.

In addition to her practice in the Australian courts, Callista acts in proceedings before international courts and tribunals. She appears in international commercial arbitrations and investment arbitrations, including before ICSID tribunals. She also acts as counsel in proceedings before the International Court of Justice, the International Tribunal for the Law of the Sea and UNCLOS Annex VII tribunals.

Prior to being called to the Bar, Callista was an associate to the Honourable Justice Susan Kiefel AC at the High Court of Australia and research associate to Professor James Crawford AC SC. She also practised at Freshfields Bruckhaus Deringer, in Paris, London and Singapore.

Callista holds a PhD in law from the University of Sydney and a Master of Law (First Class Honours) from the University of Cambridge. She is also an associate member of 3 Verulam Buildings in London.

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