The gold standard textbook in its area for over sixty years, "Pharmaceutical Calculations" is now in its Thirteenth Edition. Every chapter has been revised and updated to reflect the basic calculations applicable to the contemporary practice of pharmacy. The thirteenth edition of "Pharmaceutical Calculations" represents a thorough update of this textbook which for over six decades has met the needs of students in this important subject area. One of the most apparent changes in this edition is the inclusion of learning objectives for each chapter. The intent is not only to define the purpose and direct the student's focus but also to provide a basis for self-assessment following completion. Another important addition, appearing in the Introduction, presents a step-wise approach in solving calculations problems which should prove beneficial to students toward understanding and building confidence. It is part of "Doody's Core Titles 2009".