Since 1983 Istvan Mayer has been delivering lectures at Budapest University that are mainly attended by chemistry students who have already studied quantum chemistry in the amount required by the (undergraduate) chemistry curriculum of the University.
The exact coverage may vary from year to year, but Istvan Mayer usually concentrates on the general principles and theorems and other basic theoretical results which he foresee will retain their importance despite the rapid development of quantum chemistry. He commonly organize his lectures by treating the subject from the beginning, without referring explicitly to any actual previous knowledge in quantum chemistry-only some familiarity with its goals, approaches and, to a lesser ex tent, techniques is supposed.
This book is basically derived from the material of Istvan Mayer’s lectures. The special feature, distinguishing it from most other textbooks, is that all results are explicitly proved or derived, and the derivations are presented completely, step by step. True understanding of a theoretical result can be achieved only if one has gone through its derivation.