A publicly known economist, he has worked as a consultant to a number of foreign companies in Bulgaria and has been an integral part of Bulgarian political life through the centre right party of the former Bulgarian king Simeon Saxe Koburg-Gotha. Karolev has also been an elected Sofia city councilor.

Since 1993, Karolev has occupied top management positions at the Balkan Advisory Company, the Bulgarian Stock Exchange, the ECM-Bulgarian Post Privatisation Fund, the Europa Capital Management and the Barents Group of KPMG Consulting.

He is experienced in privatisation advisory, mergers & acquisitions, project management, business development and project finance and private equity management.

Currently, he is the CEO and co-owner of the Balkan Advisory Company, which provides corporate finance/project finance/capital markets and foreign investment services. He was appointed advisor to the minister of the economy in November 2014.