Mariana focuses her practices on handling international arbitrations and advising on other international law issues. She previously served as legal advisor for the Argentine Attorney General's Office (Procuración del Tesoro de la Nación), then as its deputy director, defending the Argentine Republic in its international disputes. In those roles, spanning 2007 to 2017, she represented Argentina in investment arbitration proceedings under the auspices of ICSID, UNCITRAL and the ICC, and supervised local proceedings in national jurisdictions, including the US, Belgium, Switzerland, France, Spain, Japan, Germany and the UK. She has also actively participated in the negotiation of international investment agreements, including bilateral treaties and free trade agreements, on behalf of Argentina.