3Rs for the public

Many scientists who use animals in their research are committed to finding alternatives and ensuring high standards of animal welfare, but there is always more that can be done. The NC3Rs was set up to help scientists replace their use of animals and, where this is not possible, reduce the number of animals used and refine the care of the animals to keep pain and suffering to a minimum. There are many ways to achieve these aims, which are known collectively as the 3Rs.

In the UK, animal research that can cause pain or suffering is regulated by the Animals (Scientific Procedures) Act 1986 with the Home Office as the lead government department. The law permits the use of animals in research as long as there is no alternative. Where their use is unavoidable, it requires that scientists only use the minimum number of animals and take steps to limit any pain, suffering or distress.

How many animals are used in research?


How are animals used in research?


Why are there concerns about animal research?

What are the 3Rs?

The principles of the 3Rs were first proposed in 1959 and stand for:


Avoiding or replacing animal use e.g. using cell cultures, computer modelling, or human tissue or volunteers.



Where animal use is necessary, keeping numbers to the minimum e.g. using statistical methods to determine the smallest number of animals that can be used in an experiment.



Where animal use is necessary, minimising pain and suffering and improving welfare e.g. using pain relief and providing housing that allows animals to perform their natural behaviours.

We have produced a short video introducing the 3Rs and their scientific importance. This was designed for training scientists, technicians and students, but is useful for anyone interested in learning more about animal research, the 3Rs and the work we do. It includes case studies relating to each of the 3Rs from researchers whose work we have funded.

What does the NC3Rs do?

The NC3Rs is an independent UK-based scientific organisation dedicated to the 3Rs. We were set up in 2004 in response to the House of Lords Select Committee report on Animals in Scientific Procedures, which recommended the establishment of a national centre to help advance the 3Rs.

We work with scientists and organisations from across the life sciences sector, including universities, industry and regulatory authorities, both in the UK and internationally. As well as funding scientific research into the 3Rs, we support the development of 3Rs technologies and drive changes in policy, regulation and practice. We engage with the scientific community through collaborating on research projects, running events and producing guidelines and other resources, including our website. Find out more about who we are and what we do.

Learn more and get involved

While much of our work is aimed at scientists, we also have some projects aimed at the public, as well as projects carried out by researchers we fund, areas of our website written for a more general audience and resources produced by other organisations. You can find links to these below.

Watch and label videos of lab mice in their home cages to help improve their welfare with this citizen science project from MRC Harwell and the NC3Rs.
This article by NC3Rs-funded researcher Dr Rachel Tanner explains the 3Rs for a younger audience.
A Science Animated video on how NC3Rs-funded researchers at King’s College London are using caterpillars to replace mice in antibiotic research.
NC3Rs-funded researcher Dr María Duque-Correa tells us about her work to tackle whipworm infection through 3Rs research and schools outreach.
We have taken part in this annual science festival since 2014. Learn more about our 2019 event via our blog post.
This article in "The Biologist" magazine shares highlights from our 2019 Research Review.
A course from the European Schoolnet Academy aimed at supporting teachers to incorporate the 3Rs into their lessons.
Videos by NC3Rs grant holder Dr Marloes Peeters, sharing her work on developing biosensors to replace the use of animals.
An article by NC3Rs grant holder Dr Donna MacCallum on her work developing new ways to study fungal infection without the use of animals.
Two short films produced by the Swedish 3Rs Center on how computer models can replace and reduce the use of animals in research.
Learn more about ESTIV's in3 Project, which aims to create lab- and computer-based tools for assessing the safety of chemicals.