Then it dawned on me that I'd forgotten to update Lizzie's microchip information when I left Yakima last year. If she were picked up by a good samaritan who scanned her for a chip, they'd get the address of someone who no longer lived in Yakima, and whose phone had been disconnected!
How many of you have changed address or phone number since you had your dog microchipped? Did you remember to notify the company? I couldn't even remember what company Lizzie was registered with--there are several microchipping companies out there now--but I did remember Lizzie had gotten it at Airport West Animal Clinic. So I called there, got the number of the microchip company (in this case, it was "Home Again"), and called the company to register the address change.
Microchips only work if the information on them is traceable to you. Don't forget to update! If you don't have the paperwork anymore, just call the vet who implanted the chip, and she'll give you the contact info you need.