Although there are a large number of software development methodologies for standalone software, little effort is being paid into investigating specialised methodologies that target the development of Distributed Applications (DAs) in the era of Internet and Web-based applications. Rather than focusing on business models, developers usually spend considerable effort in implementing connectivity between software components that comprise these applications. Since a large number of competing technologies exist, these solutions face serious technology-migration and design reuse problems. This paper advocates approaching the design activity from a business rather than technological perspective by defining a service-oriented software architecture that satisfies the functional requirements in a particular domain. The paper also suggests identifying existing or new design patterns to capture common business process functionalities and fulfil the non-functional requirements. For evaluation purposes, we are applying our approach to Capital Market Systems (CMS) through the development of a prototype system using Web Service technology.