Concordance also referred to in medicine as (compliance, adherence, or capacitance) describes the degree to which a patient correctly follows medical advice given by a medical professional. Most commonly, it refers to the medication or drug compliance by the patient, the use of medical appliances and the attendance of counseling or other courses of therapy.  Both the patient and the health-care provider affect Concordance. A positive physician-patient relationship is the most important factor in improving Concordance. However the high cost of prescription medication may also have bearing on Concordance breakdown.