Old Second Bancorp, Inc. announced that Louis L. Weinzelbaum joined the Bank as Group President, Senior Managing Director. Louis was most recently with MB Financial Bank where he served as Group President of the Professional Services Group. Alan H. Kohn joined the Bank as Group President, Senior Managing Director. Alan was most recently with MB Financial Bank where he served as Group President for their Healthcare Banking Group. Donald J. Clark joined the Bank as Senior Vice President, Commercial Banking. Don was most recently with MB Financial Bank where he served as Managing Director/Senior Vice President with their Commercial Banking Group.