CPTED design methods currently typically lack adequate means of inspection and review of: the design  and implementation; underlying reasoning; foundation of design decisions;  and any checks for CPTED causing adverse outcomes.

Program logic models offer a way of improving CPTED design processes through addressing these issues.

Program Logic Models

Program logic models provide a formal basis for evaluating CPTED programs and interventions at all stages in their implementation.

Any program or intervention comprises five phases:

  1. Events prior to any work on the program or intervention
  2. Identifying the need and scope of the program or intervention
  3. Designing the program or intervention
  4. Implementing the program or intervention
  5. The outcomes and changes following the implementation of the program or intervention

The program or intervention comprises only the middle three phases. The  benefits or otherwise emerge as outcomes in phases 4 and 5.

Phase 1 offers the basis of a reference condition prior to the design proper.The design and development of the program or intervention occurs in phases 2 and 3 and many  implementations in phase 4 (which may also include redesign and modification).

The development of CPTED interventions typically follow exactly these five phases in the same manner:

  • Phase 1: Prior situation with crime related concerns
  • Phase 2: Identifying the situation as one in which CPTED resources should be committed
  • Phase 3: Design of CPTED intervention
  • Phase 4: Implementation of CPTED intervention
  • Phase 5: Outcomes resulting from CPTED intervention post-implementation

Inputs, outputs and outcomes

Program logic models distinguish between inputs, outputs and outcomes as follows.

In program logic, each of the three phases, 2, 3 and 4 of developing and implementing the program or intervention has inputs and outputs.

For example:




2: Commitment of resources

Crime data, social data, political pressure, management decisions…

Commitment of resources, outline program plan, project aims, objectives and intended outcomes, budgets; overall timeline,…

3. Design of program

Guidance from phase 2; human, technical, financial and infomatic resources

Detail written design of program ready to be implemented; written evaluation and amendment strategy; detailed timeline; detailed budget; management strategies and plans

4: Implementation of program

Design of program and its plan for implementation and management

Implementation staff employed and managed to undertake the implementation; resources used in implementation; implementation occurs; evaluation of implementation occurs; project completion process is undertaken; report written on three stages of the project

 The outcomes of the program or intervention are the external effects and changes resulting from the implementation of the program or intervention in the world.

The outcomes of a program or intervention contrast with and are totally different to the outputs of the program or intervention. The outputs are the internal products of the program design and implementation.

CPTED design failures

For successful CPTED interventions, the outcomes are as intended and result from the intended outputs of the implementation of the intervention.

A program or intervention may, however, have no or insignificant outcomes in spite of having outputs exactly as planned and specified.

Similarly, it is possible there can be outcomes and change following a program or intervention that are not caused by the outputs of that program or intervention.

Worse is when the program or intervention produces outcomes that are adverse or opposite to what was intended.

All of the above may occur when the design of the program or intervention is flawed or based on faulty information, assumptions or principles.

Benefits of Program Logic Model for CPTED

The program logic model with its combination of program intent, inputs, outputs and the reasoning for them provides a straightforward tool for identifying the potential for problematic outcomes of CPTED. 

Identifying CPTED problematic outcomes and the causes of them by application of program  logic models offers benefits for several aspects of CPTED and Criminology. It provides a sound basis for identifying:

  • Missing or faulty data used as inputs;
  • Erroneous assumptions used as inputs and as the basis for designing outputs
  • Flawed design and management of implementations; and, in the limit;
  • Where improvements are needed in criminological theory and CPTED principles.


In conclusion, viewing the creation of CPTED interventions (and design features) as similar to social program interventions via program logic models, offers a powerful tool for addressing several design process weaknesses in CPTED.