Algebraic structures.- Automata.- Complexity.- Learning.- Logics and languages.- Trees and graphs.- Words and strings.

This book constitutes the proceedings of the 15th International Conference on Language and Automata Theory and Applications, LATA 2021, held in Milan, Italy, in March 2021.

The 26 full papers presented in this volume were carefully reviewed and selected from 52 submissions. They were organized in topical sections named: algebraic structures; automata; complexity; learning; logics and languages; trees and graphs; and words and strings.