Andrew Walmsley

Our Impact

Evaluating the impact of the projects that we support is critical to ensuring that we are backing conservation programmes and strategies that can make a real difference to the fate of orangutans and their forests.

Thanks to our long-standing field presence in Sumatra, a network of respected scientists, and partnerships with organizations, governmental agencies and academic experts, we are embarking on a key project to measure and evaluate the effectiveness of various approaches to conservation in Sumatra. As part of this focus on impact, we are also working in partnership with an alliance of organisations that share our vision, towards establishing agreed measures for monitoring progress.


An evidence-based approach to conservation enables us to ensure that we are using resources wisely. Tracking projects over time helps determine why some strategies are successful and others are not, enabling us to focus on scaling up those that have the greatest potential outcomes for Sumatra’s wildlife, forests and people.

These are some of the questions our evaluation project aims to answer:

  • What is the impact of reforestation on orangutan populations?
  • What is the economic impact of protecting rainforest on the human population living in that area?
  • What is the impact of community education and agroforestry projects on deforestation rates?


In terms of measuring our outcomes, here are some of our key achievements to date:

1,566,263 trees planted


124 orangutans rescued




local people have participated in training to support conservation-friendly livelihoods

Value for money

Not only are we proud of what you have helped us to achieve, we are also proud of the fact that our projects represent extraordinary value for money:
Rainforest in Sumatra at sunset

For every £1 we raise to help orangutans, just over 3p is spent on fundraising.


For every £1 we spend on fundraising, we turn this into £21 for projects and campaigns to protect orangutans and their habitat.


Zac Mills

An adult sumatran orangutan

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