Evgeny Sklyanin’s contributions have been key to the development of quantum inverse scattering techniques, and his discoveries concerning the algebraic structure of integrable systems brought novel concepts to mathematics, including classical R-matrices, Sklyanin brackets and Sklyanin algebras. He was the first to provide, via particular examples, ideas that have inspired the discoveries of quantum groups and Yangians, opening new areas in mathematics. He pioneered the investigation of integrable systems with boundaries, and his work on the separation of variables in integrable systems revealed inter alia new identities for special functions.