With globalization, environmental problems and significant failures in corporate governance, business ethics is perceived to be of increasing importance. This is particularly so for IS because of the huge social effects of new technologies. Yet there has been relatively little discussion of ethics in the IS literature and no clear consensus has emerged. This paper argues that Habermas’s discourse ethics can make a major, and practical, contribution. After outlining some major ethical theories and how they have been interpreted in business ethics and IS, the paper details the development of discourse ethics. Discourse ethics is different from other approaches to ethics as it is grounded in actual debates between those affected by decisions and proposals. Recognizing that the theory is rather abstract, the final section discusses how it can be pragmatized, with the help of existing soft and critical methodologies, to become a basis for business and IS ethics. Some brief linkage is made with specific IS topics including Web 2.0, open source software, the digital divide and the UK identity card.