Quintin was admitted as a lawyer in 2012 and was called to the Bar in 2014.

Quintin has authored a textbook in negotiation and is an adjunct senior lecturer at the University of Sydney.

At the Bar, Quintin has a general practice. He regularly appears in commercial, tax, equity, constitutional, maritime, property, consumer, tort and crime matters. He is experienced in representative proceedings (class actions). Quintin regularly appears unled in intermediate appellate courts. He regularly runs unled trials in the Federal Court, NSW Supreme Court, Federal Circuit Court, District Court, Local Court, as well as arbitral, NSW and Federal tribunals.

A full list of his publications is available here.

Quintin has been recognised as preeminent in Doyle's Guide Leading Transport Barristers – New South Wales since 2022.

Recently, Quintin was also recognised by Chambers and Partners in Band 2 for Shipping: The Bar. with respondees noting: “He is very bright.”, and “Quintin has been doing shipping a long time and has a very good reputation.”
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