Hussein is a Partner at Withers LLP in London, Head of Public International Law and Co-Head of International Arbitration at the firm. He is also Co-Head of the firm's Middle East and North Africa Special Interest Group.
Hussein has extensive experience of working on international legal and dispute resolution matters in London, Paris, New York and South Africa for almost 20 years. He has worked as counsel and advocate on arbitrations under all the major rules, including ICSID, UNCITRAL, LCIA, ICC, SCC and SIAC Rules, as well as in ad hoc arbitrations. His clients include governments, multinational corporations and international organisations. He has served as counsel in State-State proceedings before the International Court of Justice and in national courts, including the courts of England and Wales, on public international law issues. Hussein's public international law practice includes advising governments and international organisations on international investment law, constitutional and human rights matters, sovereign immunity, energy and natural resources, international humanitarian law, sanctions, the law of the sea and treaty and legislation drafting.
Hussein is recognised as a leading lawyer for public international law and international arbitration by all the major legal directories. Chambers and Partners notes that Hussein "has an outstanding analytical ability" and Chambers Global refers to him as "an outstanding lawyer, combining a great attention to detail with a view of the big picture". Legal 500 states that "the practical and solutions driven Haeri is outstanding" and that "he combines huge intellectual powers with great client handling and gives straight-to-the-point advice".