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Mechanisms – A missing component in your theory of change?

What’s new in theory of change

Our new ten steps to theory of change introduces the concept of ‘mechanisms’. It’s a fairly new idea in a theory of change context, reflecting the feeling that something is missing from the standard theory of change terminology of activities, outputs, outcomes and impact. What’s missing is how we want charitable services or campaigns to be experienced by people, and how we want people to respond so that outcomes and impact are more likely.

We believe this gap can be filled by adding the concept of mechanisms of change, inspired by the realist approach to evaluation, which stresses how contexts interact with mechanisms to achieve outcomes.

What are mechanisms?

A good way to think about mechanisms is as a point of connection between activities and outcomes. Here’s why they’re different:

  • Mechanisms are not activities, because they relate to your target group rather than what you do. For example, if I deliver a football coaching session to young people (my activity), then my mechanisms are about how I want those young people to engage with the session. Do they listen to me? Do they take part enthusiastically? Do they have fun? Do they work together? Do they end the session feeling that they have achieved something?
  • Mechanisms are not outcomes, because they are not yet changes for people. People having fun and feeling they have achieved something only becomes an outcome when they take these feelings away with them. For example, when the experience of overcoming a challenge through football (mechanism) gives a young person greater confidence about themselves that endures (outcome). It then becomes an impact when they use that confidence to do better in school or another aspect of life.

Mechanisms exist between these two concepts. They occur where you describe how you want people to engage with your activities; the kind of relationship you establish; and the thought processes you want them to go through in order to achieve the outcomes and impact you want. Mechanisms are sometimes subtle or hard to grasp, so throughout this article we highlight them in bold.

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Why do mechanisms matter?

This space between activities and outcomes is important. Mechanisms are the things that interventions cannot work without. They are the causes of change.

To illustrate, if a young person does not have the feeling of overcoming a challenge through my football session, then they cannot—according to my theory of change—go on to feel more confident. It is not the session itself but rather that feeling the young person has that will be the cause of any positive change. So by thinking about mechanisms we are considering the key question of causality – how change it is sparked or triggered. You can even think of mechanisms as the ‘magic’ – the special thing you need to happen to really make a difference.

To give you a different example from a campaigning context. Say I want to use an email campaign to raise awareness of the lack of green spaces to play football. The mechanisms would be that my target audience reads the email, understands it, feels concerned about the issues raised and inspired or motivated to take action. Then, if this awareness is sustained or people take action, these would be outcomes. Again, note how the mechanisms, underlined in bold, are imperative to any successful outcomes being achieved.


Why have mechanisms been missing?

We are not alone in identifying this gap. In other theories of change we have seen mechanisms mixed up with ‘activities’, ‘outputs’ or ‘very short-term outcomes’. They often appear in the ‘assumptions’ stage of a theory of change process. But ‘assumptions’ is a nebulous concept, often done at the end, so mechanisms have been confused with other things and relegated to an afterthought. We believe they need to be front and centre.


How can I identify ‘mechanisms’ in my thinking?

Mechanisms occur whilst people are experiencing your ‘activities’, services or campaigns or ‘in the moment’. We have found that the most valuable prompt to help you think about mechanisms is to ask yourself: “What do I want people to be thinking, feeling or doing whilst they are experiencing my service or campaign?”

Another good approach is to look at each outcome in your theory of change in turn, and ask yourself what needs to be happening during your activities to trigger or cause that outcome. In a campaigning context, a good way to think about mechanisms is as the ‘messages’ that you want target groups to pick up or take from your work. Our new 10-step guidance on theory of change includes a few further prompts to help you think about them (see step 6).

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Why are mechanisms so powerful/useful?

There are five main ways in which treating mechanisms as distinct improves theories of change.

  1. Treating people as individuals. Without thinking about mechanisms we imply that people will respond to our activities like robots. They read a leaflet and instantly know more and behave differently. Actually, for that leaflet to work it has to be understood, it has to feel relevant, readers have to believe they will be able to apply the information to their own lives. People are individuals who make choices – consciously (thinking) and unconsciously (feeling). It is imperative for charities to think about what they want those choices to be.
  2. They reveal hidden or tacit assumptions about services and campaigns. Sometimes mechanisms, like understanding a leaflet or engaging with a service, might seem obvious, so you might wonder why we need to include them at all. Well, arguably the point of the theory of change approach is to bring what seems obvious to the surface, so it can be discussed and agreed. More often than not, thinking about mechanisms reveals vital things that are only partly understood, or whose significance is not appreciated. For example, we recently worked on a theory of change for an organisation promoting healthy food by providing community meals, and it was through thinking about mechanisms that they realised how important it was to generate interest and excitement in the food – so discussing and celebrating it, as well as providing it to them.
  3. They are the best focus for discussions about service quality and replication. Mechanisms highlight intended causal processes, so they are a good starting point for thinking about ‘quality’. This comes from asking how best to design and deliver servies to encourage mechanisms to happen.
  4. They help you establish the right performance indicators. Mechanisms focus on how you want activities to be experienced, so they reveal what is most important to be checking first of all or immediately – and therefore the most valuable performance indicators.
  5. They tend to be the most meaningful part of a theory of change for those actually doing the work. As facilitators we find that talking about mechanisms is the best part of doing a theory of change – especially with front line staff, volunteers and beneficiaries. This is because mechanisms are what staff themselves are working towards, what they feel are important: On a daily basis, they are not trying to get young people into employment or build resilience, they are trying to build trust, to do something that makes them feel positive, get a different take on things. Frontline workers know the importance of mechanisms, and when you ask questions about them they light up, because they get to talk about what really matters in their work.
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The addition of the ‘mechanisms’ is one of the main ways in which our approach to theory of change has developed over the last few years. We have found it helps people to consider important questions and gives a distinct label to factors that are integral to success. Our upcoming full guidance will offer more detail, including the situations where mechanisms are more or less useful and whether to include mechanisms in theory of change diagrams. In the meantime if you have any thoughts on this topic we’d love to hear from you.

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