I was first admitted to practice in 2001 having graduated with the equivalent of first class honours at UNSW. While at law school I won the Law Book Company Prize for Criminal Laws and the Minter Ellison Prize for Trial Process making it clear what my future professional career was going to be. Before being admitted, I appeared as a law clerk in most criminal jurisdictions up to the NSW CCA. I lectured at UNSW Law School in the areas of evidence, litigation, and criminal procedure and worked for Stephen Odgers SC on an early edition of Uniform Evidence Law. I was also the foundational editor of the Australian Journal of Human Rights. Since being admitted I have been published on human rights and sexual assault law, and presented CLE papers on practice and procedure at the NSW and Australian Crime Commissions.

Since 2004, I have been in continuous practice as the principal of Katsoolis + Co. Solicitors + Attorneys, a Sydney-based law firm specialising in high level criminal defence. For over twenty years when you engage me you get me and my experience and expertise from the beginning of your case to the end. I have successfully defended every type of crime in the criminal calendar at all court levels including the High Court of Australia and have featured in numerous best criminal lawyer lists in the news media. The firm prides itself on not just following precedent but making it. I hit the ground running with a succession of successfully defended high profile criminal matters particularly murder and large scale drug supply and have made my name as a serious crime specialist ever since. In 2021 and 2022, I was a finalist in the Lawyers Weekly Australian Law Awards in the Sole Practitioner category, the only criminal lawyer to have done so.

I have run matters in just about every court in New South Wales from Bega to Broken Hill. I have also successfully defended criminal matters in every other Australian State and Territory. I have acted in matters in Asia, the United States, and even Sweden (for a client charged with impersonating George Young of Vanda & Young / AC DC).

I have appeared in related jurisdictions such as the Children's Court, the State Parole Authority, the Coroner's Court, the Federal Court, the Mental Health Review Tribunal, as well as in RMS, EPA, Workcover, ASADA, RMS, and ATO prosecutions. I have acted in investigative bodies such as the Crime Commission, the Law Enforcement Conduct Commission and the ICAC. I have also conducted proceedings in family law, employment law, administrative law, personal injury claims (particularly against the State), intellectual property and defamation proceedings. Wherever the litigation is difficult and heavy, I am here to help to achieve absolute wonders for the client. As a testament to my profession repuation and proven track record, I am now acting for third generations of families and routinely accept referrals from the Bench and the profession.