Canada tries out traffic roundabouts in an effort to reduce traffic in some of the country's busiest areas. Some cities are reluctant to replace traffic lights with roundabouts because of safety concerns.
"The new vogue for roundabouts follows intensive study by Canadian traffic engineers of their adoption south of the border. They concluded that roundabouts produced less congestion, fewer serious accidents and lower emissions. Best of all, unlike lights, they work even when the power grid fails."
"Quebec is enthusiastic, issuing guidelines in 2002 for proper construction of le carrefour giratoire; it now has about 80 roundabouts. In Ontario the Waterloo region (which includes Cambridge) is a pioneer, but the provincial government worries about pedestrian safety."