This book provides a compact but comprehensive treatment that guides the reader through the important applications of operational amplifiers. The author uses his extensive classroom experience to guide readers toward a deeper understanding of key concepts of operational amplifier circuits. The NI(R) Multisim(TM) is used throughout the book to analyze and design the circuits. The book is designed to serve as a textbook for courses offered to undergraduate and postgraduate students enrolled in electrical and computer engineering. The prerequisite for this book is a first course in electric circuits.