Always have your dog (or cat) microchipped! This is the easiest method to get your dog or cat back, if they escape. Microchips are done at the vet's office, and are registered to your name and number. Likewise, if your dog gets lost, someone would likely take the dog to a vet clinic to be scanned for a chip.
Seems obvious? Right? Sadly, many people neglect this super simple step of putting a collar with proper identification on their animals. If they get lost, how will people return them to you? I also suggest adding a line saying "microchipped" on the engraving so people are aware.
Hundreds of Thousands of Dogs are born each year "accidentally". The best and easiest way to stop the overcrowding of shelter populations is to spay or neuter your animal. Think about this: A dog can have 2 litters a year. Per litter, there can be 6-10 dogs. So, in 2 years you have produced 24-40 dogs who need homes!
Think about this: Around 2.7 million adoptable dogs and cats are euthanized each year in the United States simply because they do not have homes. They sit at the shelter, healthy & adoptable, waiting for loving homes. Just go visit a shelter, you'll fall in love!