Crime Prevention Through Environmental Design

Crime Prevention Through Environmental Design, or CPTED (pronounced sep-ted), is a crime
prevention philosophy based on the theory that proper design and effective use of the built environment can lead to a reduction in the fear and incidence of crime, as well as an improvement in the quality of life.

The best time to apply this philosophy is in the design phase, before a building or neighborhood
is built. You can also successfully apply it later, but retrofitting an existing environment can sometimes be costly.

The use of CPTED can reduce crime and fear by reducing criminal opportunity and fostering
positive social interaction among legitimate users of space. A legitimate user means one who is
using a space for its intended purpose. The emphasis is on prevention rather than apprehension and punishment.

Three Key Principals

There are three basic, overlapping principles in the CPTED concept. In order to get a better understanding of the concept, let us consider these:

Natural Surveillance: We need to create environments where there are plenty of opportunities for people engaged in their normal behavior to observe the space around them. By designing the placement of physical features, activities and people in such a way to maximize visibility,
natural surveillance occurs.

Natural Access Control: Most criminal intruders will try to find a way into an area where they will not be easily observed. Limiting access and increasing natural surveillance keeps them out altogether or marks them as an intruder. By selectively placing entrances and exits, fencing, lighting and landscaping to control the flow of or limit access, natural access control occurs.

Natural Territorial Reinforcement: An environment designed to clearly delineate private space does two things. First, it creates a sense of ownership. Owners have vested interest and are more likely to challenge intruders or report them to the police. Second, the sense of owned space creates an environment where “strangers” or “intruders” stand out and are more easily identified. By using buildings, fences, pavement, signs, lighting and landscaping to express ownership and define public, semi-public and private space, natural territorial reinforcement occurs.

Why the emphasis on “Natural”: Historically, the emphasis has been on the target hardening
approach to crime prevention. Relying on mechanical (locks, security systems, alarms, monitoring equipment, etc.) and organized (security patrols, law enforcement, etc.) crime prevention strategies to make the target harder to get into and can create a fortress effect and “feel” unsafe. This traditional approach tends to overlook the opportunity for natural access control and surveillance. By natural, reference is made to the crime prevention by-product that comes from normal and routine use of an environment.

The CPTED theory advocates that all possibilities for natural crime prevention be exhausted,
prior to the involvement of the mechanical and organized strategies. The CPTED approach is
much more user friendly and customer service oriented than the traditional target hardening
approach.

Example: A multiple story office building is designed with a large lobby with elevators and a
directory and is expected to be “self serve”. Over time, crimes occur in the lobby area; purse
snatches, an assault or two, criminal damage, etc. The owner of the building installs CCTV to
monitor the situation. Eventually guards are employed to monitor the CCTV and further down
the road, to watch people come and go. By now, people do not feel comfortable coming here.
They feel that it is unsafe, they are being watched on video cameras, and NOW things are so
bad that they have to have a security guard in the lobby all the time.

A better approach, the CPTED approach, would have been to design in the opportunity for
natural surveillance from the beginning; possibly a receptionist, or a coffee stand. Put some
type of activity into the unassigned space in order to create natural crime prevention. In
addition, the CPTED approach is much more customer service oriented. It serves the same
purpose as the guard, but does not look as harrowing. In fact, it is much more inviting.

The Three D'S:Cepted

CEPTED involves the design of the physical space in the context of the bona fide user of the space, the normal and expected use of that space, and the predictable behavior of the users and offenders. CPTED emphasizes the connection between the functional objective of space utilization and behavior management. We must differentiate between designation of the purpose of space, its definition in terms of management and identity, and its design as it relates to function and behavior management. By using the “Three D’s” as a guide, space may be evaluated by asking the following types of questions:

Designation:

• What is the designated purpose of this space?
• For what purpose was it originally intended?
• How well does the space support its current use or its intended use?
• Is there conflict?
  

Definition:

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

Design:

• How well does the physical design support the intended function?
  
• How well does the physical design support the desired or accepted behaviors?
  
• Does the physical design conflict with or impede the productive use of the space or the proper
  
• functioning of the intended human activity?
  
• Is there confusion or conflict in the manner in which physical design is intended to control
  behavior?
  

Once these questions have been asked, the information received may be used as a means of
guiding decisions about the use of human space. The proper functions have to be matched with
space that can support them. The design has to assure that the intended activity can function
well and it has to directly support the control of behavior.

Strategies in Action

Following are a few examples of CPTED strategies in action. In each there is a mixture of the three CPTED concept keys that is appropriate to the setting and to the security or crime problems. Some of the examples were created in the direct application of CPTED. Others were borrowed from real life situations that were observed to be working. The most basic, common thread is the primary emphasis on naturalness—simply doing things that you already have to do a little better.

• Provide clear border definition of controlled space.
  
• Provide clearly marked transitional zones that indicate movement from public to
  semipublic to private space.
  
• Relocate gathering areas to locations with natural surveillance and access control or to
  locations away from the view of would-be offenders.
  
• Place safe activities in unsafe locations to promote natural surveillance of these activities to
  increase the perception of safety for normal users and risk for offenders.
  
• Redesignate the use of space to provide natural barriers to conflicting activities.
  
• Improve the scheduling of space to allow for effective use, appropriate “critical intensity”
  and temporal definition of accepted behaviors.
  
• Redesign or revamp space to increase the perception or reality of natural surveillance.
  
• Overcome distance and isolation through improved communication and design efficiencies.
  

CPTED Goal

By including CPTED principles in new construction from the design stage, we can make the built environment safer from the start, rather than waiting for crime problems to develop and depending on law enforcement to handle them after the fact. By reviewing existing problem areas and applying the CPTED principles, those problems can be turned around.

The goal of using the CPTED philosophy is to design and build safer, more productive, userfriendly environments, reducing costs and liability, and ultimately the improvement in the
quality of life. There are no hard and fast rules in CPTED. This is not good and that bad. CPTED is about sharing ideas and asking questions.