About Constantine
Constantine Gionis serves as the principal of Gionis Legal & Advisory Pty Ltd, a distinguished legal practice established as per the Legal Profession Act (NSW) 2004. Admitted as a solicitor in 1993, Constantine brings a wealth of experience in general commercial law, contracts and tendering, dispute resolution, and regulatory investigations and prosecutions. His expertise extends to Australian Consumer Law and governance and compliance, having received the Highly Commended Award for Excellence in Government Legal Services by the Government Solicitors’ Committee, Law Society of NSW.
Constantine's academic background is robust, including a Bachelor of Arts in Economics and Political Science from the University of New South Wales, a Diploma of Law from the Legal Profession Admission Board, and a Master of Laws from the University of Sydney. He completed his Graduate Diploma of Legal Practice at the College of Law, NSW.
His professional journey began at ASIC, where he honed his skills for six years before taking on significant roles such as Corporate Lawyer and Deputy Company Secretary at Thales Australia. Here, he addressed complex projects and tenders in defence and civil domains and managed corporate acquisitions and disposals. His tenure as Group General Counsel & Company Secretary at Cement Australia saw him advising on extensive legal and regulatory issues within the industry.
In 2013, Constantine founded Gionis Legal & Advisory, where he leads in the establishment of new business ventures, corporate restructuring, and competition law advice. His proficiency in contracts, corporate governance, and compliance has made him a trusted advisor in sectors such as government, defence, manufacturing, and shipping. A fluent Greek speaker, Constantine also provides strategic guidance on management of regulatory investigations and commercial disputes. His leadership extends to mentoring junior lawyers and delivering legal and compliance training to non-legal executives.
