Some common behaviour problems which your dog may exhibit:
Pulling on the lead
Lunging at dogs and people
Jumping up at people
Have a fear of noises
Become aggressive
Bark continually
Suffer from anxiety
Bark whilst in the car
Destroy your furniture or possessions
Become obsessive
Refuse to come when called
Toileting in the house
Picking at his/her food
With any behavioural issue, to ensure the cause of the problem is treated, it is important to look at the whole picture, not just the symptoms.
I use only natural methods.

Covering the North East of England
Cleveland (Teesside), Durham, North Yorkshire, Northumberland, Tyne & Wear