A specialist firm for the moments that matter most.

Mark O'Brien Legal is a Sydney law firm built around one idea. When your reputation, your business or your rights are under attack, you need lawyers who go further than standard legal representation.

Our lawyers bring more than 40 years of experience in defamation and media law, reputation and crisis management, commercial litigation and white collar crime. They have been recognised as leading media lawyers by Chambers and Partners, The Legal 500, Best Lawyers and Doyle's Guide.

Our mission

To protect our clients' rights and interests with strategic, results driven legal solutions. We combine deep expertise with fearless advocacy and pragmatic advice, so that individuals, organisations and institutions can face complex legal challenges with confidence.

How we work

• Principal led. Every matter is run by one of our three principals, not delegated to a junior team.
• Fast. Reputational harm compounds by the hour. We are available around the clock for urgent matters, including weekends.
• Discreet. Many of our clients are household names. Confidentiality is built into how we communicate, file and negotiate.
• On both sides of the table. We act for claimants and for publishers, so we know how the other side thinks.

Who we act for

Politicians and public officials, chief executives, high profile individuals and their families, broadcasters and publishers, sportspeople and entertainers, and charities, schools and institutions. More on who we work with.