Cigarettes are smoked by over 1 billion people, which is nearly 20% of the world population. There is a gradual decline in smoking prevalence in areas of developed economy. For example, the smoking prevalence of Hong Kong people aged 15 or above dropped from 23.3% in 1982 to 10.5% in 2015. 1 Smoking is the single most important preventable risk factor for premature death and chronic diseases, including cancer and cardiovascular disease. Smokers die 13 years earlier than non-smokers. Smoking is responsible for 7,000 deaths and nearly 6 million deaths a year in Hong Kong and worldwide respectively. For various reasons, the prevalence of smoking is higher among patients than the general population. 30.7% of hospital patients were current smokers compared to the 21% of average population in UK. 2 The prevalence of smoking in patients with acute limb fractures was more than twice the general population in Australia. 3 The direct medical cost and indirect cost (loss of productivity from sick leaves and premature deaths) is up to 11.3 billion Hong Kong dollars a year. The direct medical cost of smoking accounts for 5.7% of global health expenditure and the indirect cost of smoking totaled to 1.8% of the world's annual gross domestic product (GDP). 4 Over 7,000 known toxins (70 of which are carcinogenic) are released and inhaled during smoking. These include nicotine, carbon monoxide and hydrogen cyanide etc. Carbon monoxide reduces oxygen carrying capacity of red blood cells and formation of carboxymyoglobin reduces oxygen storage in muscles. Hydrogen cyanide impedes cellular oxidative metabolism. Nicotine has multiple adverse effects including inhibition of osteoblast formation and function (impaired bone healing and non-union), impairment of wound and tendon healing (wound complications), impairment of immune response (wound infection), vasoconstriction, increased platelet adhesiveness (tissue hypoxia) and addiction. All these contribute to the increased risk of surgery in patients who smoke, whether current smoker or ever-smoker. Smoking exposes patients scheduled for surgery to risk increases of 20% in-hospital mortality and 40% in major complications including deep infection, pneumonia, unscheduled intubation, pulmonary embolism, ventilation >48 hours, stroke, coma >24 hours, cardiac arrest, myocardial infarction, transfusion >5 unit, sepsis, septic shock. 5 There is ample available evidence that current smoking increases complications in almost all type of surgery. Smoking is associated with surgical site infection and postoperative wound infection after spine surgery, total joint arthroplasty and fracture fixation; fracture non-union, non-union after spinal fusion, ankle fusion, osteotomy and internal fixation and bone grafting for scaphoid non-union; worse outcomes after spine surgery for lumbar disc prolapse, spinal stenosis and cervical myelopathy; periprosthetic joint infection and lower survivorship after total hip, knee arthroplasty, shoulder arthroplasty; worse outcomes after Contents lists available at S...