At the Paws and Whiskers Pet Spa, dogs and cats showed off their cute costumes as photographers practiced taking their portraits.
The big event is Sunday at the Pacific Street Dog Park.
Pets and humans are invited to vie for the prizes and check out animal-friendly vendors.
After Sunday's competition, don't forget to stop by the Abbot Kitty Lounge at the pet spa if you want to take home some very special portraits of your furry family members.
It's only $40 for a half-hour photo shoot and all the pictures.
You can always stop by in person or visit the Abbot Kitty Lounge website to book an appointment.