Purpose – The internationalisation of business and the process of globalisation raise many ethical issues about acceptable norms of conduct on the part of corporations. This article aims to evaluate whether there is progress in establishing standards for international business ethics. Design/methodology/approach – The paper explores whether the case for a global standard of business conduct can be grounded and justified in rational argument. Findings – As a moral minimum, corporate ethical codes need to rule out what the management believes to be clearly unacceptable behaviour. The distinction between thick and thin moral rules is particularly important in wrestling with the rights and wrongs of international business ethics. A good deal of room needs to exist for the local interpretation of these codes, but there are a number of situations where universal standards have to be enforced in the host country. Originality/value – This paper summarises the progress made in establishing the field of international business ethics. And it identifies and discusses the evidence on the effectiveness of ethical codes in improving international business practice.