This document provides an overview of the topographical and surface anatomy of the thorax, with a focus on the regional lymph nodes and their clinical relevance. It describes the bony framework and contents of the thoracic cavity, as well as relevant surgical approaches and procedures. Key points covered include the boundaries of the thoracic inlet and outlet, landmarks on the ventral thorax surface, thoracic incisions and operations, muscles and innervation patterns, lymphatic drainage pathways including those of the breast, and reconstructive procedures following breast surgery.