Many distributed real-time and embedded (DRE) applications require a scalable event-driven communication model that decouples suppliers from consumers and simultaneously supports advanced quality of service (QoS) properties and event filtering mechanisms. The CORBA Notification Service provides publisher/subscriber capabilities designed to support scalable event-driven communication by routing events efficiently between suppliers and consumers, enforcing QoS properties (such as reliability, priority, ordering, and timeliness), and filtering events at multiple points in a distributed system. The standard CORBA Notification Service is insufficient, however, to enforce predictable communication needed by DRE applications and does not leverage Real-time CORBA capabilities, such as end-to-end priority assignment or scheduling services. This paper makes three contributions to the study of scalable real-time notification services for DRE applications. First, we describe the requirements of the OMG Request for Proposals (RFP) on Real-time Notification, which seeks solutions to the problem of enforcing real-time properties by enhancing the standard CORBA Notification Service. Second, we explain how we have addressed key design challenges faced when implementing a Real-time Notification Service for TAO, which is our CORBA-compliant real-time Object Request Broker (ORB). We discuss how we integrate Real-time CORBA features (such as thread pools, thread lanes, and priority models) to provide real-time event communication. Finally, we analyze the results of empirical benchmarks of the performance and predictability of TAO's Real-time Notification Service. These results show that the static real-time assurances provided by Real-time CORBA are maintained within the more flexible context of TAO's Real-time Notification Service.