The three Rs are scientific guiding principles that augment the efforts for the ethical and more humane treatment of animals in research. In 1959, the term ‘Rs’ was first described by W. M. S. Russell and R. L. Burch in the book- “The principles of Humane Experimental Research”. Right from the onset, these principles have been adopted by national as well as international legislation to measure and to check their animal research practices. The principles have also been embedded into the directives of organizations, which undertake or aid animal research in any direct or indirect way. It is to be noted that, many countries have explicitly adopted the principles of 3Rs in their modes and directives. The UK has implemented the 3Rs through a national organization named as National Centre for Replacement, Reduction, and Refinement of animals in research, which is also called as NC3Rs. 

A LOWDOWN ON THE 3Rs

The preeminent pillars of the 3Rs are the following three principles:

• Replacement
• Reduction
• Refinement

Let us understand the significance of these three principles in detail.

• Replacement: In the original context, this principle was against the use of vertebrates for research. They placed emphasis on the fact that sentience leads to suffering. Use of invertebrates instead of vertebrates was chosen to be an acceptable alternative. But recent research and interpretations have emphasized on the use of non-animal methods for executing various researches. A need is being propagated to develop various models, tools, and techniques that totally replace the use of animals in any kind of research. However, NC3Rs backs the use of certain invertebrates in research practices. They have propagated relative replacement instead. Keeping in mind the above deliberations, we can bifurcate this principle into two categories, namely Full replacement (total avoidance of animals in any kind of research and testing) and Partial replacement (it restricts the use of animals which cannot take any kind of suffering but allows for the use of invertebrates and other species as the experiment might deem fit).
• Reduction: The main motive of this principle is to reduce the number of animals used in research. We have to understand that using animals in research is a common practice because the physiology and to some extent features of animals are closest to humans. Animals can also be trained to mimic any desired human condition, which might be a prerequisite for testing. But this entire practice is not just unethical but also criminal in the context of its scope and capacity. Any kind of research done on the animals inflicts tremendous torture, pain, and sufferings. In order to curb this practice, various modules and frameworks are being developed those restrict the number of animals used in research work. Proper and strategic planning needs to be undertaken that elucidates properly the need and scope of having an animal in the experiment in the first place. Also, unnecessary usage of animals in the name of research can be quelled. The experiments are required to be thoughtfully planned and executed with the output for optimum usage of animals for experimentation. 
• Refinement: The crux of this principle is to modify and tweak the methods used in experimentation in order to make them less agonizing for the animals being used in research. This includes conducting a well thought of research and development in the fields of animal welfare so as to devise strategies that minimize their pain during experiments. Various technologies and contemporary researches pertaining to the matter need to be explored and studied. Some of the techniques that can be adopted might include the usage of less invasive experiments like indoctrinating admissible dosage of anesthesia or other analgesic regimes for relieving the pain or trauma. Animals should also be trained to cooperate willingly with the proceedings and demand of the research work in order to reduce the trauma and distress. Apart from these, the environment that berths the animals should also be conducive to their needs and requirements. A harrowing and dingy habitat also causes unnecessary trauma to the animals and instills in them a sense of fear and duress. 

The need for research and development shall find greater impetus in the coming times owing to an ever-evolving holistic environment. Disruptive technologies have taken over the world in every known field. Adhering to these principles is cardinal for a balanced and ethical approach towards research and development involving the usage of animals in some way or the other.