In the 1990s, Weber has become one of the strongest voices of the Romanian civil society, being involved in a number of national and international non-profit organization, such as the International Helsinki Federation for Human Rights (Vienna), where she was Vice-chair (1994–1996), or the Association for the Protection of Human Rights in Romania – Helsinki Committee (APADOR-CH), where she was Co-chair (1994–1999).

She also held classes on the protection of human rights in the context of international relations, at University of Bucharest, Faculty of History (2003–2004).

Subsequently, she was appointed by the European Commission as Chief of the EU Election Observation Mission for the 25 January 2009 Constitutional Referendum in Bolivia and she was also Chief Observer for the EU EOM deployed for the presidential and legislative elections that took place in Bolivia on 6 December 2009.

In May 2010, Renate Weber was invited by the European Commission to lead the EU EOM deployed for the May–September 2010 electoral cycle in Burundi, Africa.

Her dismissal was declared unconstitutional by the Romanian Constitutional Court on 29 June, and she was reinstated in her position on 6 July 2021.