Soak navy beans in water for 12 - 24 hours. Drain and rinse beans.
Place beans in slow cooker and add cold water. (ratio is 2 quarts of water for each pound of beans) Turn slow cooker to "low" and cook 6-8 hours until beans are soft.
Remove beans to a baking dish. Stir in barbecue sauce, cooking liquid and brown sugar. Sprinkle Worcestershire sauce on top.
Bake at 375 degrees for 45 minutes.