There is no more helpless feeling than when you find out your dog is missing. If you didn't see them leave, you have no idea what to do first. Here are some tips that I hope will help
If your pet runs off or is missing:
If your dog runs off, assign one person to follow them so that their whereabouts are tracked. This person is your eyes, not the dog's rescuer. They should have a cell phone to keep in contact with you.
Dogs rarely move very far from where they escaped.
Call for help. Create a list of friends that you can call to come and help you search. Use a phone tree and ask the first person you call to help by calling others.
Assign each person an area and tell them to stay in their quadrant. Some dogs need to calm down before they will show themselves. If you've moved on in your search, you may miss your dog.
Assign one person to start printing up flyers. Another to distribute them.
Offer a reward on the flyers.
Contact your homeowners association. Many of them have an email contact list of the neighborhood. Ask them to send out an email blast.
Call animal control and local vets and animal shelters.
Enlist the help of your microchip host. Many send out emails to your neighboring areas. Companies like findtoto.com make robo-calls to the area where the dog was lost.
Put a listing on craigslist in your area. Give pertinent information about the dog and offer a reward.
If your dog is timid, bring another dog that your dog may come to. Tell searchers not to pursue your dog as this will push them farther away.
Make sure your dog's tags are up to date and that they are wearing their collar with your current phone number.
Get your dog microchipped. If they are found and turned in to a vet or animal shelter, they will be scanned and you will be contacted.
If your dog is larger than 15lbs consider having them wear a GPS collar. There are companies that make these collars so if your pet gets lost you can pinpoint their exact location on a phone or computer.
If you think for one second that your dog might run off if given the chance, don't give them the chance. Lock gates, use tethers and leashes, keep them away from doors that could be opened unexpectedly.