My 4 year old dog is wetting in the house, how can I stopp him?

If a sudden change in behavior occurs, it's always best to do a once over with the vet to rule out any medical issues such as UTI's or bladder infections and even incontinence. Have there been any changes in the home? Any moves? New people in, old people out? Are you kenneling? When does she have these accidents the most? When you are home or while you are away? Have you had her for the entire 4 years? There are many reasons a god can regress in house breaking, but we will need a bit more info first. Is she spayed? Are there other dogs in the home? And how long has she been doing this for?