Abstract: The theory of Yangians was introduced by Drinfeld in the 1980s as a systematic approach to solving the Yang-Baxter equation: every irreducible finite-dimensional representation is equipped with a rational R-matrix obtained by normalising the action of a universal R-matrix. In this talk, I will provide a generalisation of this result for Yangians of affine type and their representations in category O. - This seminar is part of the activities of the Project PRIN 2022S8SSW2 funded by the European Union – Next Generation EU.