Blind Variation and Selective Retention, or BVSR for short, is a principle from cybernetics describing change in evolutionary systems. BVSR is better known as the core concept of the theory of evolution. Although it has its origin in Darwinian evolution, BVSR is a more general principle; for example, it can also be applied to memetic evolution or genetic programming. The term is little used outside of cybernetics.

BVSR describes a repeated process of two steps -- blind variation and selective retention on a population (of animals, religions, programs, etc.).