Can one be an unethical ecotourist? Here I set out to show that this question is neither trivial nor straightforward. Most definitions of ecotourism, even the more restrictive (Buckley, 1994) focus on observable criteria such as tourism products and settings, management of environmental impacts, guided interpretation for clients, and perhaps some contribution to conservation (Buckley, 1994, 2003; Fennell, 1999; Weaver, 2001). Certainly, there are complexities in interpreting and implementing any of these (Buckley, 2003), but these are second-order. Demanding that ecotourism be defined by ethical rather than behavioural considerations is very different. Definitions of ethics, whether philosophical, professional or general, are based on morals and require individuals to make moral judgements. This is not the same as requiring people to follow rules of behaviour, even if these rules are labelled as codes of ethics rather than codes of conduct or legal regulations.