Within domain-based service environments, service discovery through appropriate matchmaking procedures remains a key challenge. In particular, the consideration of additional context information and the need for dynamic and fast service publishing cause high demands on the according automatic matching procedures and the service description structures they are operating on.Within this paper, we introduce a model to abstract the complexity of service descriptions for both the service provider and the consumer. Therefore, the internal representation of service descriptions is transparent providing only a suitable access model for services. Service Consumers are enabled to access services by specifying the effects while service providers are provided with a model to classify their service by categories. Within this approach special emphasis is put on the consideration of service compositions during the matching procedure.