Here is the book that helped popularize Prolog by making it accessible to a wide range of readers. This edition includes much new material and improved presentation. It will serve as an invaluable reference work for anyone who wants to study and use Prolog as a practical programming language.
From the reviews of the fifth edition:
"This is the fifth and the most recent edition of a legendary book ... . It was probably the first introductory Prolog book and it is still the most gentle introduction to Prolog for everyone, including non-computer scientists. ... the book is as great as ever as an introductory text for Prolog. When a newbie asks for an introduction to Prolog, the best advice is still Clocksin & Mellish." (Bart Demoen, TLP-Theory and Practice of Logic Programming, Vol. 5 (3), 2005)