The logical solution is to limit vehicle speeds in areas where pedestrians are present, because speed determines impact severity. With every small increase in speed, pedestrian deaths go up even faster. The authors cite research concluding that about 5 percent of pedestrians hit by a vehicle traveling 20 mph will die. Lowering speed limits alone can bring small improvements. In most studies, the authors report, actual travel speeds dropped by a quarter or less of the posted speed limit reductions.
Effective enforcement is more critical.
Even the presence of enforcement isn't enough. The consequences of getting stopped for speeding have to be meaningful enough to keep drivers from knowingly taking the risk. It's impossible to put a police officer on every street, so cameras are a practical means of increasing the perception of enforcement. Red-light cameras already have won favor in jurisdictions around the country. On the other hand, the designs of roadways often encourage drivers to go faster than the posted speed limits.