John S. Koudounis
John Spiro Koudounis is an American business executive who serves as the President and Chief Executive Officer of Calamos Investments. Previously, he was President and CEO of Mizuho Securities USA Inc., a subsidiary of the Japanese banking and holding company Mizuho Financial Group. He is a regular commentator on financial news programs.
Koudounis is the founder of the and a member of the Leadership Council at Concordia, as well as the Bretton Woods Committee. He is a board member of the National Hellenic Museum, a patron of Prince's Trust International, and an executive advisory board member for the SEAL Future Foundation.
Early life and education
Raised in Chicago, Koudounis attended Niles West High School in Skokie, Illinois, where he was class president. He played basketball and American football. He interned for Senator John Chafee and at Kidder Peabody, where he worked during the Black Monday stock market crash in 1987. In 1988, he graduated from Brown University in Providence, Rhode Island, receiving a double major in International Diplomacy and Economics.Career
Koudounis began his financial career at Merrill Lynch. He then joined ABN AMRO's North American branch, where he spent 12 years as the head of fixed income.In 2008, Koudounis joined Mizuho Securities USA Inc. as executive managing director and head of fixed income, where he oversaw trading, sales, and investment banking activities. In the following year, under his leadership, the fixed income division reported record earnings for the firm. In 2010, he was appointed president and CEO of the company, at the time becoming the youngest CEO of a Wall Street firm at 44 years old.
In early 2016, Koudounis was the designated CEO of Calamos Investments, an investment firm headquartered in Naperville, Illinois. He was appointed by founder John Calamos, Sr. as part of Calamos' succession plan. Koudounis leads the firm's business activities, including executing the firm's growth strategy and expanding the firm's global footprint.
Koudounis is the founder of the Chicago CEO COVID-19 Coalition, an organization created in 2020 during the COVID-19 pandemic to provide relief for the city and bring Chicago's business leaders together. The initiative focused on four areas in COVID-19 recovery: food, shelter/homelessness, counseling services, and personal protective equipment. The coalition distributed over $1.5 million in proceeds from its televised fundraising.
Koudounis is a member of the Leadership Council at Concordia and the Bretton Woods Committee. He is a member of the board of trustees of the National Hellenic Museum, and an executive advisory board member for the SEAL Future Foundation. He is a founding board member and executive committee member of The Hellenic Initiative. He is a member of Leadership 100 and Chairman of the Metropolis of Chicago Foundation. In 2016, he was inducted as an Archon of the Ecumenical Patriarchate in the Order of St. Andrew.