"The Tipping Point," as defined by Malcolm Gladwell, "is that magic moment when an idea, trend or social behavior crosses a threshold, tips and spreads like wildfire."

"Broken Windows" is a theory developed by criminologists stating, "if a window is broken and left unrepaired, people walking by will conclude that no one cares. Soon more windows will be broken. A sense of insecurity follows that spreads from the building to the street which it faces, sending a signal that anything goes. In a city, relatively minor problems like graffiti, public disorder … are the equivalent of broken windows, invitations to more serious crime."

You can apply the "broken window" theory to neighborhood traffic safety. Speeding and stop sign running may be viewed as minor offenses. Yet, if drivers speed, run stops signs and show general disregard for the safety of anyone on or near the street, it creates a sense of unease among neighbors.