I have a Yorkshire Terrier who is 7 years old.  She is well house trained and is very good.  We have the occasional accident that can't be helped.  She has recently started urinating all over the place.  I open the back door for her to go out and she looks and then backs away.  The next thing I know she has urinated somewhere in the house.  I don't think it is weather related as she goes out in all weathers in the morning and at night.  I don't think this can be related to an infection as she is being given the opportunity to go out and she doesn't do it all the time although it is getting more and more frequent.  Can anyone help me please with a reason why she may be doing this?  Thank you.

If you have an infetion you do not always know you need to go, believe me. Would take the girl to a vet for some investigation, no adult bitch would start to become dirty without some good reason and the best place to start would be the vets.

Please get her checked out by a vet to determine if there is an infection, don't just go on your own 'feelings' - a urinary infection left untreated can cause kidney damage.  If there is no infection, register with the board and I'm sure people will be more than willing to help.....