In this article, the focus of which is research with children, Peter Allmark considers ethical issues in relation to both quantitative and qualitative research. Guidelines on the ethical conduct of research with children focus primarily on issues to do with quantitative research (e.g. RCPCH 2000). For this reason, this article tries to draw out points of particular importance to qualitative research. It begins with some assumptions and points of terminology, before briefly describing the history of the development of ethical regulation. It then discusses specific ethical issues that arise when researching with children. These are placed into three main categories: scientific validity, welfare, and rights and dignity.