The Development Act 1993 provides that 'no development may be undertaken unless the development is an approved development' [s.32]. However, not all acts or activities in relation to land are regarded as 'development', and not all development requires a formal approval. Accordingly, it is important to understand the legal meaning of the word 'development'.

Development is defined in the Act [s.4] in very wide terms and it includes building work, a change in the use of land, or land division. Building work includes construction as well as the demolition or removal of a building. The Act now catches all those highly publicised disputes involving developers who sought to knock down existing buildings or structures before seeking planning permission. A change in the use of land constitutes development, even if no building work is undertaken. For example changing the use of a house from a residence to a restaurant or doctor's surgery would constitute development.

The Act defines land to include land covered with water and therefore includes things like permanently moored houseboats and pontoons within the definition of 'development'. It also includes acts or activities which are declared by the Regulations to constitute development. This means that to ascertain one's rights and obligations it is necessary to refer to the Regulations as well as to the Act. Generally speaking, minor activities such as building cubby houses or fences do not usually require development approval but home extensions, garages or major earth moving projects do. If in doubt, it is usually safest to talk to your local council about your plans to ascertain whether formal development approval is necessary.