Today businesses have to change the way that they operate frequently because of advances in technology and business-to-business communication. To be able to keep up with these changes in business operations it is necessary to separate business rules and procedures from system functionality. By defining a component-based business model, it is possible for the business expert to specify and modify business operations without re-designing the automated system controlling the business operation. We propose a business model consisting of three different components where domain expert in each area can define and customise a component with minimum interaction with other components of the business model. Our main objective behind the component-based approach in business model specification is twofold. One is to be able to define a model that is easily customisable by domain expert, eliminating the need to develop a new system when changes to the business process or organisation have been introduced. Secondly this approach will reduce the time, cost and disruption to the business. We have mapped this model to an XML representation which best can describe the hierarchical and semi-structural format of business model. A system for B2B communication has been developed using this approach.