Water: Do not drink bottled water, but whenever possible favor tap water, which is safe and controlled. Tap water is better Nutrition: Limit the foods of animal origin and industrial production. Give preference to fruits, vegetables, whole cereals and legumes, better if fresh, from your local area, and cultivated according to current season and in a biological way. ISDE #1 Ionizing Radiation: X-rays should not be carried out unless a specific clinical indication. Do not use oversized surgical sets or open unnecessary single-use materials; instead, adopt custom sets, assembled for specific procedures and follow the “Do not open it if you don’t need it” rule, according to Circular Economy principles. Do not unnecessarily leave lights, computers, electromedical equipment, and Anaesthetic Gas Scavenging Systems (AGSS) turned on when operating rooms are not in use; instead, implement energy-saving strategies (set-back mode) when indicated. Do not perform surgical hand scrubbing with water and antiseptic soap before every procedure; instead, after the first wash of the day, prefer the use of alcohol-based hand rubs, if hands are not visibly contaminated. Do not perform routine clinical interventions in the perioperative pathway, such as antibiotic prophylaxis, histological examinations, and other procedures; instead, apply Lean Management and Sustainable Healthcare principles to ensure clinical appropriateness and rational resource use. Do not dispose of healthcare waste as “hazardous/infectious waste” unless strictly necessary; instead, ensure correct separation and recycle, choosing the disposal method with the lowest carbon footprint. Biodiversity. Antibiotics: only when indispensable! For common respiratory infections (colds, rhinosinusitis, cough/bronchitis, flu syndromes) and bacteria in the urine without symptoms, do not prescribe antibiotics, because generally they are useless, and expose patient and family to risks, both present and future. The rule is to avoid them, leaving to doctors’ autonomy the assessment of any exception. Air: do not consume fuels of “fossil” origin (coal, oil, gas). Whenever possible, use renewable energy (solar, photovoltaic, wind, geothermal, energy-saving buildings) and reduce the use of private vehicles in the city by encouraging the use of: bicycles, public transport, shared private vehicles, pedestrian mobility. Limit travel by plane as much as possible by favoring the use of the train, not necessarily at High Speed. Try to oppose against the fashion of cruise tourism.