Crime Prevention Through Environmental Design

Crime Prevention Through Environmental Design or CPTED (pronounced sep-ted) contends that perceived safety in a community can be created by designing a physical environment that influences positive human behavior. CPTED is a process, a way of thinking about crime.

Three Key Concepts:

Natural Surveillance – Increases visibility: A design concept directed at keeping intruders easily observable. Uses Lighting, landscaping and the placement of windows to increase the ability to see what's going on in an area. When used to its greatest advantage, it maximizes the potential for deterring crime because a criminal's behavior is more easily noticeable to anyone passing by.

Natural Access Control – Controls access: A design concept directed at controlling access to potential targets. This is created by using and incorporating physical and mechanical means of access control.

Territorial Reinforcement – promotes a sense of ownership: This concept uses physical design to create or extend a feeling of ownership and sends a message that the property belongs to someone. This is accomplished by embodying all the principles of Natural Surveillance and Access Control. It uses fences, signage, landscaping, and lighting to define property lines and clear distinctions from public and private.

Three-D Concept/Space Assessment Process

To begin to understand putting CPTED concepts into practice you should do a space assessment using the 3-D's - Designation, Design, Definition.

Designation - All human space has some designated purpose.

  • What is the designated purpose of the space? –what is it supposed to be used for?
  • What was the original intended purpose for the space?
  • How well does the space support its intended use or its current use?
  • Is there conflict?

Definition – There are social, cultural, legal or physical definitions for all human space that prescribe the desired and acceptable behaviors.

  • How is the space defined?
  • Is it clear who owns the space?
  • Where are its borders?
  • Are there social or cultural definitions that affect how the space is used?
  • Are the rules, legal or administrative, clearly set out and reinforced in policy?
  • Are there signs?

Design – All human space is designed to support and control the desired behaviors.

  • Is there confusion or conflict in the manner in which the physical design is intended to control behavior?
  • How well does the physical design support the intended function?
  • How well does the physical design support the desired or acceptable behaviors?

CPTED or Security Surveys are a service that most law enforcement agencies provide for residential and commercial properties. In most agencies the task of completing a formal written security survey falls in the realm of the crime prevention officer's job, however, while on scene at a variety of calls for service, patrol officers can conduct an informal survey for the public. Contact your local law enforcement agency to see if this service is provided.