New forms of cooperation like collaborative business scenarios require flexible and semantic integration of heterogeneous processes come from various companies. Heterogeneity cross-organisational business processes needs adaptation of existing concepts for business process management. A shared ontology can encapsulate heterogeneity in business process model and offer common concepts to different partners. In this paper, an ontology based approach is proposed that shows how to integrate business processes using service ontologies and Web services composition. It combines both ontologies and Web services in order to address the processes integration problem.