Titles in the Complete series combine extracts from a wide range of primary materials with clear explanatory text to provide readers with a complete introductory resource. A public authority must have the legal power to act; if that power is conferred by statute, it may also specify the procedure that must be used prior to an action or a decision being taken. This is what is known as a ‘statutory procedure’, because it is specified in a statute. The statute may, for example, require the authority to give notice of its intention to take action in a certain way, to consult interested groups, or to tell individuals that they have the right to appeal from an adverse decision. If the authority does not comply, then this is a breach of the statutory procedure and may be reviewed as a procedural impropriety. This chapter discusses the judicial review of procedural impropriety. It covers the rules of natural justice; the right to be heard; legitimate expectation; the detailed requirements of natural justice; the rule against bias; and Article 6 of the European Convention on Human Rights.