By Toby Lowe

Why is the idea that we can measure our impact to understand how well we are performing fundamentally flawed? Why is it impossible to “demonstrate your impact” in complex environments?
Although the idea of measuring impact is seductive, almost all useful social change is achieved as part of a complex system. In other words, your work is a small part of a much larger web of entangled and interdependent activity and social forces.
The systems map of the outcome of obesity, shown in the figure below, illustrates this perfectly – it shows all the factors contributing to people being obese (or not), and all the relationships between those factors.
This is the reality of trying to make impact in the world – your actions are part of a web of relationships – most of which are beyond your control, many of which are beyond your influence, quite a few of which will be completely invisible to you.
All of these things combine with your actions to create impact in the world. Let’s work this example through using the obesity systems map. Say that you’re one of the people operating in the bottom right corner of this system – you’re providing “healthcare and treatment options” to address obesity.