I don't know if this has been discussed in the past, but I'm curious as to why fenced yards are common in some parts of the US, and not in others. The city that I work for require block fencing for all new housing developments. We've had a developer ask for an exception, to use vinyl-coated wood, instead of block. For jurisdictions that allow fence-less housing developments, my city's block fence requirement probably seems onerous. What is your take on fenced or unfenced yards?