Because of high market competition between services in today’s multi-provider environment, means to regulate quality of service (QoS) is required to guarantee for providers’, users’ and other actors’ rights when purchasing/selling a service. There are already a multiple of existing telecom services available to users, and with implementation of next generation networks (NGN), or similar future network propositions, the number of services and different providers are expected to increase rapidly. More than one actor may be involved in delivering a service, and the needs for regulation of QoS between actors involved in delivering a service are therefore even more present in NGN.Creating a model with effective traffic and network handling methods for packet based networks, using tools such as MPLS, DiffServ, routing mechanisms and SLAs is one of the future goals. This thesis concentrates on methods of how such a model can be realized, using different tools.One proposal of regulating QoS is to implement service level agreements (SLA) as standard, regular agreements being used whenever an exchange of service resources is made. An SLA should include service description, user’s and provider’s rights in terms of delivery, faults, service degradation, monitoring, pricing etc. Other quality of service terms which are service specific are often included in attachments or as individual QoS agreements. SLAs can also be used by customers to compare similar services, that way improving the competing environment.Standardizing SLAs has been a main focus for many standardization organizations; how can the SLAs guarantee quality of service, as opposed to free market competition and legal regulation. A naïve perspective may be to say that the laws in Norway and free market competition are sufficient to regulate the multi-provider environment, but there are reasons why it is not so. Service Level Agreements are used to ensure that all relationships in an actor network environment, be it service providers, network operators, customers etc, operate in the “correct” way; ensuring quality of service, traffic engineering, and economic and legal issues. This is why the content of SLAs is one of the “hottest” topics among big actors in the telecommunication sector.