In a client-based ALS, the client and service provider enter into an agreement on the services to be provided. For example, a company may negotiate with the IT service provider that manages its billing system to define its relationship and specific expectations in detail. These agreements are widespread in some sectors, such as. B hosting companies and other delivery services, where customers have high expectations to achieve almost perfection. Having an ALS is very useful for a company that offers a service, as it helps create and maintain realistic expectations for customers.