Two sectors of the healthcare domain in which CDSSs have had a large impact are the pharmacy and billing sectors. There are commonly used pharmacy and prescription ordering systems that now perform batch-based checking of orders for negative drug interactions and report warnings to the ordering professional. Another sector of success for CDSS is in billing and claims filing. Since many hospitals rely on Medicare reimbursements to stay in operation, systems have been created to help examine both a proposed treatment plan and the current rules of Medicare in order to suggest a plan that attempts to address both the care of the patient and the financial needs of the institution.