This book presents the OCTOPUS method, providing a systematic and effective approach for developing object-oriented software for embedded real-time systems. The method is based on the popular OMT and Fusion methods, but also embodies common practice found in real-time systems. It applies proven object-oriented techniques, while matching the specific needs of real-time systems, such as concurrency, synchronization, communication, handling of interrupts, hardware interfaces and end-to-end response times. The method defines an incremental development process with well integrated phases and clearly linked components, covering requirements specification, system architecture and subsystem analysis/design. The book includes transition from design to implementation and features process priorities and timing analysis. Two extensive case studies demonstrate this in practice.