Kostas is a fellow at the Hertie School in Berlin and President of the Commission for the Environment, Climate Change, and Energy (ENVE) at the European Committee of the Regions. He also works as a strategic consultant and leads the opposition in Athens. He served as Mayor of Athens from 2019 to 2023, Governor of Central Greece from 2014 to 2019, and Mayor of Karpenissi from 2011 to 2014. Bakoyannis previously worked at the Greek Ministry of Foreign Affairs and held positions as an executive manager in the private sector in Athens. He has also served in the European Parliament in Brussels and at the World Bank in Kosovo. He is a council member of the European Council on Foreign Relations. In 2022, King Philippe of Belgium awarded him the honour of "Grand Officier de l'Ordre de la Couronne."