These contributions, written by the foremost international researchers and practitioners of Genetic Programming (GP), explore the synergy between theoretical and empirical results on real-world problems, producing a comprehensive view of the state of the art in GP. In this year¿s edition, the topics covered include many of the most important issues and research questions in the ¿eld, such as: opportune application domains for GP-based methods, game playing and co-evolutionary search, symbolic regression and ef¿cient learning strategies, encodings and representations for GP, schema theorems, and new selection mechanisms. The volume includes several chapters on best practices and lessons learned from hands-on experience. Readers will discover large-scale, real-world