Donald J. Clark has been named senior vice president, Commercial Banking with Old Second National Bank. He will operate from the Chicago—Loop location.

He will be responsible for developing and growing commercial banking, specializing in the senior housing and healthcare space.

Clark has more than 30 years of commercial banking and financial services experience. Prior to joining Old Second, he served as managing director, senior vice president, with the National Healthcare Banking Group of MB Financial (now Fifth Third Bank).

Old Second Bancorp is a diversified bank holding company headquartered in Aurora, IL.