Research on grid computing has produced significant results in design and implementation of different computational, data-intensive, and service-oriented grid sys-tems. However, important issues such as component-based application design and QoS management have received less attention. In particular, for real-time grid applications it is difficult to specify and satisfy QoS requirements. Our QoS-aware component based approach presented in this paper, allows grid application developers to separate concerns of what level of quality is required from how that level is to be achieved. In addition, it addresses how QoS requirements can be reliably satisfied when an application is deployed on even a minimally provisioned instance of the component-based grid middleware platform.