The book is written to appeal to practitioners and students, to lawyers and economists. It is not only a textbook in economics for first-year graduate or advanced undergraduate courses, but also a book for all those who wish to understand competition issues in a clear and rigorous way. Exercises and some solved problems are provided. The book is also accessible to readers who are not familiar with modern economics, as the formalisation of the material covered in the main non-technical sections is relegated to separate "technical" sections.