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Section 4

Logic Models and Theories of Change

A Theory of Change is a comprehensive description, illustration and explanation of how and why a desired change is expected to happen in a particular context. It maps out what a programme does (its activities or interventions), the nature of such activities and how these lead to desired outcomes being achieved. It does this by first identifying the desired long-term outcomes  - in this case, employability  - and then works backwards from these to identify all the intermediate outcomes that must be in place (and how these related to one another causally) for the goals to be achieved (Center for Theory of Change, 2021).

The Theory of Change is a tool that helps explain the relationship between the problem being addressed and the strategies used to address it, showing why and how change takes place (The Open University, 2017).


A theory of change, sometimes referred to as a programme theory, is different from a logic model in that:

  • A theory of change starts with ends (desired outcomes or impacts) – what are the core components of employability? – and works backwards to develop appropriate means (i.e., it bases activities on your desired outcomes or impacts and identifies rationales for all activities).

  • Fundamental to a theory of change is the outlining of the assumptions underpinning the programme (which are missing from a logic model) – how and why will the programme outputs generate the required outcomes? It is concerned not just with what you do, but why you do it. 

  • It is explanatory rather than simply descriptive. It explains why you do something not simply what you do.

This approach shifts the focus from families of programmes (sports projects) to families of mechanisms (i.e., how do the programmes work?). The key issue is the assumed programme mechanisms which may inform the design and delivery of the programme but are not always clearly identified and defined. The key idea of using theory as a basis for evaluation is that policy makers’ and programme providers’ beliefs and assumptions underpinning any intervention can be expressed in terms of a theory of change - a sequence of causes and presumed effects (Weiss, 1997). Not only does this approach seek to describe actual mechanisms (i.e., how does the programme work?), but it “aims to surface the theoretical underpinnings of the program in advance and use the theories to help structure the evaluation” (Weiss, 1997: 510).

The World Bank (2004:10) promotes the use of theory-based evaluation because:

" [it]… in-depth understanding of the working of the program or activity – the ‘program theory’.

In particular it need not assume simple linear cause-and-effect relationships…..By mapping out the determining

or causal factors judged important for success, and how they might interact, it can then be decided which steps should be monitored as the progress develops, to see how well they are in fact borne out.

This allows the critical success factors to be identified. "

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