SurModics Inc., Eden Prairie, announced that Susan Knight, a member of the board since 2008, will become board chairwoman, effective immediately. She replaces Scott Ward, who has resigned, as has board member Timothy Nelson. The board now consists of six members, five of whom are independent. There are also three vacancies on the board. The board may seek to fill one or more of these vacancies based on its determination regarding the appropriate size of the board, its needs relative to the company's operations and strategy, and other factors. Ward and Nelson resigned over a disagreement about the working relationship between the board and the company's chief executive. Knight is the former senior vice president and chief financial officer of MTS Systems Corp.