• It will help your vet a great deal if you are able to test and observe these behaviours before visiting the clinic.
• Even if the signs are classic for separation anxiety, there could be an underlying medical problem that is causing your dog's stress level to rise.
• Once medical conditions have been ruled out, behavioural therapy can be initiated.
• Another way you can train your dog is to "practice" leaving the house.
• Remember, whatever you are attempting to teach your dog, whether they are a puppy or an old mutt, the two "P" words are the most important - patience and praise.

via dogflu.ca

1. Consult your veterinarian to get a correct diagnosis of separation anxiety.
2. Practice leaving your dog alone for short periods of time.
3. Gradually increase the amount of time you stay away.
4. Avoid overly emotional good-byes and greetings.
5. Keep your dog confined in a safe area while you are away.
6. Exercise your dog for an hour each day in places other than your yard or home.
7. Praise your dog often to build self-confidence, rather than punishing her for exhibiting frightened behaviors.

via ehow