Abstract
The Semantic Grid aims at enhancing Grid architectures by knowledge engineering techniques. The service notion is central in this approach. Service-level agreements, called contracts, are formed to define the service usage conditions. Ontology technology can form the framework to capture semantical conditions for contracts. Often, applications of Grid services involve a combination of several services. We present an ontology-based framework for service composition for the Semantic Grid. We take a process-oriented view of services, achieving an intrinsic representation of services and their composition in an ontology.