805 ILCS 5/2.25: By-laws.

Unless the power to make, alter, amend or repeal the by-laws is reserved to the shareholders by the articles of incorporation, the by-laws of the corporation may be made, altered, amended or repealed by the shareholders or the board of directors, but no by-law adopted by the shareholders may be altered, amended or repealed by the board of directors if the by-laws so provide. The by-laws may contain any provisions for the regulation and management of the affairs of the corporation not inconsistent with law or the articles of incorporation.