This volume was motivated by the Year of Prolog initiative, launched to celebrate the 50th anniversary of the emergence of Prolog through the work of Alain Colmerauer's team in Marseille. The volume editors, authors, and scientific advisors and reviewers have been the leading researchers and programmers in this field over decades, and the book represents an excellent overview of the field, its successes, and its future.After a first chapter that gently introduces the Prolog programming language using examples, the next 7 papers discuss general views of the language, possible extensions for...