Nonlinear optics is a continuously expanding field due to its wide range of applications covering temporal, spectral, polarization or spatial features of the light signals. 2023 was the celebration of 50 years since the numerical prediction of the existence of solitons in optical fiber by Hasegawa and Tappert and, to celebrate this milestone, Optics Communications invited submissions related to nonlinear coherent structures in optical waveguides involving the Kerr nonlinearity. The purpose of this Special Issue was to provide an overview of recent ongoing progress and trends in advancing the knowledge, understanding, and novel applications of optical solitons and other related nonlinear structures. Both theoretical and experimental reports or discussions were welcomed.