Ethical or socially responsible investment is one of the most rapidly growing areas of finance. New government regulations mean that all pension funds are obliged to take such considerations into account. However, this phenomenon has received little critical attention from business ethicists, and a clear conceptual framework is lacking. This paper, by a practitioner in the field, attempts to fill this analytical gap. It considers what difference, if any, lies between the terms ‘ethical’, ‘green’, or ‘socially responsible’. It also tackles (...) the difficult question of how any public form of investment can be called ‘ethical’ in an overtly pluralistic society. The paper provides an account of the historical development of ethical investment, and traces the evolution of the varying terms used to describe it. This is followed by a conceptual analysis of these terms, and a description of ethical decision‐making in this context. The paper ends by considering the role of shareholder action within ethical investment, and assesses the utility of the stakeholder model as a theoretical justification. (shrink)