Behavior problems are a common cause of frustration among pet owners. The first step in dealing with a behavior problem is to determine whether the behavior is normal or abnormal. Sometimes behaviors that are perceived as a problem or nuisance by people may be a normal behavior for an animal. If the problem is determined to be abnormal, the next step is to decide whether it is solely a behavior problem or whether it is secondary to an underlying illness. Several medical diseases including hypo- or hyperthryoidism, urinary tract disease, and osteoarthritis can cause profound behavior changes. If the doctor determines that the problem is behavioral and not an underlying medical issue, he or she will discuss an appropriate treatment plan that may include behavior modification and medication. Before embarking on any behavior program, check with your veterinarian to confirm that the problem really is behavioral and not a physical illness.