The present book "Principles of Economic Theory" is a useful "tool" addressed to both educators and students of the 3rd grade of Day General High School, the 4th grade of Evening General High School, the 3rd grade of Day Vocational High School, and the 4th grade of Evening Vocational High School.

The First Part includes the topics and answers of the Panhellenic Examinations from the year 2000 to 2007 of Day Schools (June and July resits), Technical Vocational Schools (T.E.E.) (June), as well as Evening Schools (June and July resits).

The Second Part includes the answers and solutions of the textbook that refer to the taught-examined subject matter.

The Third Part includes seven Evaluation Criteria - one for each chapter that refers to the taught-examined subject matter - and their answers.