This book provides a pedagogical guide to dermatologic ultrasound. As in any imaging field, dermatologic ultrasound is dynamic, and the area expands with the release of new technology. This textbook is a mix of the essential knowledge necessary to start and a detailed update to the dermatologic ultrasound field. This book is divided into three sections: The Requisites, Ultrasound Features of Common Dermatologic Conditions, and Practicalities. The first section details the basic information needed in dermatologic ultrasound, including technical recommendations and dermatologic concepts. The second covers major dermatologic conditions and their ultrasound presentation, including benign and malignant skin tumors, pediatric conditions, nail entities, inflammatory conditions, infections and infestations, and aesthetics. The final section covers tips for reporting and interventional dermatologic ultrasound procedures.