The edition includes condensed knowledge about modern ultrasonography, presented in the most understandable way possible from the perspective of the clinical obstetrician-gynecologist. In addition, instructions are given on how the ultrasound device can be utilized in an external medical practice. The goal is to bridge the gap in knowledge that separates the specialized obstetrician-gynecologist from those who are beginning to be trained in the application and utilization of ultrasound. The seventeen chapters of the book are divided into two major sections. The first three introductory chapters refer to the history of ultrasound and Doppler, the basic knowledge from the Physics of ultrasound and Doppler, and the safety of ultrasound. Then, Part A (chapters 4-11) titled "Ultrasound in Obstetrics" includes the basic principles governing ultrasound in obstetrics and provides detailed information on ultrasound in weeks 5-10, weeks 11-13, weeks 14-19, weeks 20-24, weeks 25-35, weeks 36-41, as well as ultrasound during labor and delivery. In Part B "Ultrasound in Gynecology" (chapters 12-17), the basic principles of ultrasound in gynecology are described, followed by ultrasound findings from the endometrium, uterus, fallopian tubes, ovaries, from the cul-de-sac and the pelvis. In both parts, both scientific data and the author's personal experience, as shaped by the application and utilization of ultrasound in clinical practice, were utilized. The photographic material of the book (1800 ultrasound images and 60 diagrams), as well as the cases presented, come from the author's personal archive.