This book presents the essentials of thoracic ultrasound. It provides practitioners (emergency physicians, resuscitators, pulmonologists) with the basic notions of thoracic ultrasound. In this book, we expose the physical bases of ultrasound, the aspect of the normal thorax as well as the frequent pathologies explored by ultrasound (pleurisy, pneumothorax, pneumonia, ...).We hope that this will help you in your daily practice and allow a better management of pleuropulmonary pathologies.