More than 30 000 people undergo heart surgery in the UK each year. A significant source of long-term morbidity following sternotomy is the tendency to form abnormal scars. Living with scars can be challenging in a social environment that values physical attractiveness. The physiology of wound healing is a complex, dynamic process that results in restoration of anatomical continuity and function. However, where the reparative processes are disrupted, wound healing can be impaired resulting in two pathological extremes: deficient healing leading to chronic wounds or excessive healing leading to hypertrophic or keloid scars. Current post-sternotomy precautions are, at best, supported by indirect evidence and have several limitations. Psychosocial distress is directly related to patient-perceived scar severity and unrelated to clinicians’ ‘objective’ rating. The potential impact of sternal scar formation should be discussed with patients pre-operatively and appropriate support (social skills training, cognitive behavioural therapy) should be offered during recovery.