His political career began as legal advisor for civil and environmental organisations in the late 1980s. As a founder of Danube Circle, he also had a significant role in environmental protection issues like preventing the construction of the Gabčíkovo - Nagymaros Dams which, according to the Danube Circle, would have damaged the habitat of a northern part of the Danube. He was one of the founders of the Hungarian Democratic Forum (MDF) in 1987, and represented that party in the Opposition Roundtable negotiations that played a very important part in Hungary's transition to parliamentary democracy. In 1989, for a short time he was member of the executive committee of the MDF.