Shared streets, the contemporary vernacular used to describe streets that have been intentionally redesigned to remove exclusive boundaries for pedestrians, bicyclists, cars, etc., work well within a special set of conditions. It is, in reality, just a new way of describing the original use of streets (see this previous post for more on that). The most promising candidates for shared streets are those where traffic volumes are not too heavy, the route is not a critical corridor for vehicular through-traffic, activities and attractions along the street are plentiful, short distance connectivity is viable, and a critical mass of pedestrians (perhaps enough to pack sidewalks at certain times) exists. A shared street may also be suitable in places where there is a desire to induce such conditions; however, care must be taken to understand the larger network effects of shifting or slowing down vehicular traffic. But in some instances, seemingly unrelated changes to traffic patterns or the effects of a coincidental collection of the above conditions sometimes go unnoticed until a street that may have been all about cars gradually shifts into something I refer to as a “de facto shared street”.