Buildings and motor vehicles are fundamental parts of the modern metropolis – and both are among the largest contributors to global carbon emissions, given the former's need for heat and power, and the latter's continuing dependence on the internal combustion engine. The good news is that sustainability concerns are at the forefront of several initiatives to shape the cities of the future. Planet Mark is an organisation that's committed to transforming society through the measurement of carbon and social data. "To keep the certification, an organisation must reduce its carbon footprint every year," explains Planet Mark's founder and CEO, Steve Malkin. "On average, certified businesses make a 16% carbon saving per employee through efficiencies in energy, waste, water, travel and procurement."

Gordon's wine bar is reached through a discreet side-door, a few paces from the slipstream of London theatregoers and suited professionals powering towards their evening train. A steep staircase plunges visitors into a dimly lit cavern, lined with dusty champagne bottles and faded newspaper clippings, which appears to have had only minor refurbishment since it opened in 1890. "If Miss Havisham was in the licensing trade," an Evening Standard review once suggested, "this could have been the result." The bar's Dickensian gloom is a selling point for people embarking on affairs, and actors or politicians wanting a quiet drink – but also for pickpockets. When Simon Gordon took over the family business in the early 2000s, he would spend hours scrutinising the faces of the people who haunted his CCTV footage. "There was one guy who I almost felt I knew," he says. "He used to come down here the whole time and steal." The man vanished for a six-month stretch, but then reappeared, chubbier, apparently after a stint in jail.