Criminologists agree that effective design can be used to reduce crime opportunities. A typical offender will assess a potential crime victim or a location before committing a crime. If the design and use of a building or place creates the perception that the costs of committing the crime are greater than its benefits, the potential offender is likely to think twice about committing crime.

Target hardening using Crime Prevention Through Environmental Design (CPTED) seeks to influence the design of buildings and sites by:

• Increasing the perception of risk to criminals by increasing the possibility of detection, challenge and capture.
• Increasing the effort required to commit crime by increasing the time, energy or resources which need to be expended.
• Reducing the potential rewards of crime by minimising, removing or concealing “crime benefits”.
• Removing conditions that create confusion about required norms of behaviour.