The ICD system of disease classification is the single most important system as all insurance companies demand that you use this system. The latest version of this is the ICD-10 code system. ICD codes have been approved by multiple cooperating parties, including the American Hospital Association, American Health Information Management Association, Health Care Financing Administration and the National Center for Health Statistics. In addition to ICD codes, current procedure terminology (CPT) codes are used to describe medical and surgical services performed by healthcare providers. Almost all insurance claims forms require a valid ICD-10-CM diagnosis code and a CPT procedure code in order for the patient to be reimbursed.