Service Oriented Architecture (SOA) is an architectural style to reuse and integrate existing systems for designing new applications. Each application is designed in an implementation independent manner using two major abstract concepts: services and connections between services. In SOA, the non-functional aspects (e.g., security and fault tolerance) of services and connections should be described separately from their functional aspects (i.e., business logic) because different applications use services and connections in different non-functional contexts. This paper presents a UML profile to graphically describe and maintain non-functional aspects in SOA in an implementation independent manner. This paper also describes how the proposed profile is used to develop secure service-oriented applications.