The Life Changes Trusts believes that alogic modelis a good way to visualise yourtheory of changeand to explain links between theory, inputs, outputs, and outcomes clearly. It can also be a good way to identify where your activity may be able to contribute to longer term or higher level (e.g. societal) outcomes set by government or funders

What is a logic model?

A logic model tells the story of your project in a diagram and a few simple words.  It shows a causal connection between the need you have identified, what you do, and how this makes a difference for individuals, communities, and perhaps more widely.

A logic model can help you to identify what you expect to happen and when.  It can therefore provide a pathway or road map for measuring progress.  It is a ‘plausible’, sensible model of how a project, initiative, or intervention is supposed to work.

The logic model process serves as the starting point for conversations around measuring progress, and can later be considered the ‘report card’ that you might use to understand whether or not you have achieved your intended outcomes.

What’s the difference between a theory of change and a logic model?

One way of explaining the difference between the two is to see a theory of change as the reasoning or thinking behind what you do, and the logic model as the representation of that thinking in diagram form.  The benefits of using a logic model approach include:

  • Focussing attention on the link between activities, processes, and desired outcomes.
  • Keeping the underlying assumptions about why things will happen at the forefront.
  • Providing clarity about how things were intended to work, and what might have to change in response to any difficulties.
  • Supporting ongoing evaluation by identifying how activities produce outcomes and focusing on each of the elements of the model to see what happens, what works, what doesn’t work, and for whom.

What does a logic model look like?

There are many types of logic model, ranging from the simple to the very complex. Different types of logic model can look at the process of change in different ways.  The example below is adapted from the Kellogg Foundation.  

  Adapted from the Kellogg model   of inputs to impact.    Source:

Adapted from the Kellogg model of inputs to impact.  Source:

You should choose an approach that suits the complexity of your project or intervention. 

One of the simplest and most effective ways to present the aims and objectives of your project, and the associated outcomes and outputs is a planning triangle.

  Source: Based on the CES Planning Triangle

Source: Based on the CES Planning Triangle

  • The Aim is the longer term outcome that our activities aim to achieve or contribute to.
  •  Outcomes are the agreed changes we want our activities to make.
  • Activites/outputs are the things we do to make the change we want.