Born in Banská Bystrica (Slovakia). He graduated from the Faculty of Law of Charles University in Prague, where he received JUDr. (JD.) in 1979 and CSc. (PhD. equivalent) in 1985. In addition, he has also undertaken studies at the Faculty of International Law and International Relations in Kiev, Ukraine and at the Institut du droit de la paix et du dévelopement in Nice, France, at the Institute of International Public Law and International Relations in Thessaloniki, Grece and The Hague Academy of International Law.
In 1986, he joined the Czechoslovak Federal Foreign Ministry as an Assistant Legal Adviser, and in 1990 was promoted to Head of the Ministry's Public International Law Division. The following year, he was transferred to the Permanent Mission to the United Nations, where he served as Legal Adviser. After 1993, he served as Slovakia's Deputy Permanent Representative from 1993 to 1994. From 1994 to 1997, he served as Slovakia's Ambassador to the United Nations. Returning to the Foreign Ministry, he served as Director of the International Law Department from 1997 to 1998, when he transferred to the post of Director-General for International Legal and Consular Affairs. After a year in that post, he was reappointed as Slovakia's UN Ambassador, serving until his election to the International Court of Justice in 2002.
He currently serves his third consequtive nine-year mandate of the Judge of the International Court of Justice that will expire in 2030.