Chest wall deformities may be present at birth, but majority of these is rarely seen prior to adolescence. They represent a wide spectrum of congenital disorders, the two most common of which deteriorate around puberty and cause either a protrusion (pectus carinatum) or a depression (pectus excavatum) of the sternum and the surrounding rib cartilages. Furthermore, these abnormalities may occur after trauma or follow prior surgical interventions. Severe forms of these deformities have been reported to be associated with reduced heart and lung function and restricted physical activity. Vast majority of these patients experience a significant psychological stress due to their visible chest deformity, which is the main reason they seek the possibility to correct their physical appearance and improve their social well-being. Chest wall deformities can be corrected using non-operative techniques, such as bracing for pectus carinatum and the use of a vacuum bell for pectus excavatum. Both techniques require high patient compliance and patience due to long-term daily treatment over a period of up to several years. Current surgical techniques aim to correct these deformities through minimally invasive procedures using removable metal bars. This chapter discusses some basic facts about chest wall deformities and provides information on treatment techniques and expected outcomes.