A relationship between an insurance company or other management entity and a self-funded plan or group of providers in which the insurance company or management entity performs administrative services only, such as billing, practice management, marketing, etc., and does not assume any risk. The client bears the financial risk for the claims. Clients contracting for ASO can include health plans, hospitals, delivery networks, IPAs, etc. A provider system wishing to capitate may contract with a TPA for ASO for certain services for which the provider group does not want to bring in house. This is a form of outsourcing. See also TPA.