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

Quintin regularly appears in commercial, estoppel, abuse of process, tax, equity, trust, jurisdictional, constitutional, maritime, property, consumer and tort matters. He is a generalist who is often briefed in cases where multiple areas of law interact.

He regularly runs unled trials in the Federal Court and NSW Supreme Court and regularly appears unled in intermediate appellate courts. He is experienced in representative proceedings (class actions).

Quintin is the co-author of The Law of Estoppel in Australia - Principles, Case Notes and Precedents, the author of Negotiation: Science and Practice and is an adjunct senior lecturer at the University of Sydney.

Quintin is recognised in a number of national and international rankings.

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