Over the last decade impressive improvements in computer and ultrasound technology have promoted a wide use of ultrasound in clinical practice. With the advent of color and power Doppler ultrasound, and more recently three- (3D) and four-dimensional (4D) ultrasound, research expansion in the field of human reproduction, obstetrics and gynecologic oncology has occurred. Ultrasound has simplified guided techniques such as oocyte collection and breast biopsy, but has also become an important technique in the assessment of the follicular growth and endometrial development, as well as in evaluation of the uterine and ovarian perfusion. Significant studies have been made in the gynecological application of Doppler sonography and screening for ovarian and uterine malignancy. In obstetrics, Doppler sonography has allowed unprecedented insight in the pathophysiology of human fetal development. In a relatively short period of time, 3D and 4D ultrasound has proved to be a useful clinical tool in almost all sections of gynecology and obstetrics. In this book the authors explain the significance of each of the discussed subjects in an effective way, by integrating important and updated information and illustrative examples. The contributors of this edition have made significant improvements, included updated information and a few unique illustrations. Each chapter has been reviewed and revised to focus on the clinicians’ needs in ultrasound practice. The educational impact of the book is further enhanced by adding a manual for sonographers and physicians entitled “Clinical Sonographic Pearls” that was created for better organization of important clinical presentation-based information.