When you talk to your neighbors and find out that cars have been stolen in the neighborhood, then you might want to consider a neighborhood watch.
When you realize you haven't talked to your neighbors in days, weeks, months, and even years, it is time to think about a neighborhood watch.
The Buddy System is part of a neighborhood watch, isn't it?
Neighborhoods with side walks, speed bumps, children playing signs help make the neighborhood safer. Having a leash law is helpful. I have never been in a neighborhood with dogs always on a leash in "their yard." Several dogs in my neighborhood have been hit by cars in the past.