<a href="https://billingexecutive.com/">Billing Executive</a> – a “Medical Billing and Coding Knowledge Base” for Physicians, Office staff, Medical Billers and Coders, including resources pertaining to HCPCS Codes, CPT Codes, ICD-10 billing codes, Modifiers, POS Codes, Revenue Codes, Billing Errors, Denials and Rejections.