Corporate liability for competition contraventions exposes companies and officers to income-based penalties; due diligence defence available. Where a company contravenes the Competition Act or related instruments, the company and every person in charge of and responsible to the company at the time are deemed to be in contravention and may be subject to income-based penalties; cartel agreements attract an annual income-linked penalty. Directors, managers, secretaries and other officers are also deemed liable where the contravention occurred with their consent, connivance or is attributable to their neglect, but a due diligence defence is available if a person proves lack of knowledge or that all reasonable steps were taken to prevent the contravention.