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.
What are the 3Rs?
The principles of the 3Rs were first proposed in 1959 and stand for:
Replacement
Avoiding or replacing animal use e.g. using cell cultures, computer modelling, or human tissue or volunteers.
Reduction
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.
Refinement
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.
Articles
A feature on two of our 3Rs Prize winners and how their work is helping reduce the use of animals in research.

NC3Rs-funded researcher Dr Rachel Tanner explains the 3Rs for a younger audience.

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.

An article by NC3Rs grant holder Dr Donna MacCallum on her work developing new ways to study fungal infection without the use of animals.

An introduction to organ-on-a-chip technology and its potential to replace animal studies, aimed at 14-19 year olds and available in English and Spanish.

Videos and podcasts
A Science Animated video on how NC3Rs-funded researchers at King’s College London are using caterpillars to replace mice in antibiotic research.

Videos by NC3Rs grant holder Dr Marloes Peeters, sharing her work on developing biosensors to replace 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.

A podcast interview with Selina Ballantyne, Licence Manager at the University of Cambridge, on why good science and good animal welfare go hand in hand.

Dr Ben Newland (Cardiff University) explains his work on cryogels, which was highly commended for the 2021 3Rs Prize.

Other resources
Our citizen science project with MRC Harwell, giving anyone the chance to get involved in improving laboratory mouse welfare by watching and labelling videos of mice in their home cages.

A course from the European Schoolnet Academy aimed at supporting teachers to incorporate the 3Rs into their lessons.
