As software is increasingly developed as part of an overall, often multidisciplinary system, traditional engineering approaches often reach their limits when faced with increasing complexity, variability, requirements, or cost and productivity pressure. Generally, reuse and product-orientation are considered promising approaches to tackle such challenges, but to fully exploit their potential require an effective product management function. Although established software process life cycle models acknowledge the importance of reuse, they do not consider appropriate product management practices, while established systems engineering life cycle models lack reuse as well as product management. -We therefore propose the integration of a process model proposal for software product management with one for enhancing system life cycle processes with reuse and product-orientation. The resulting model can be used as add-on to ISO/IEC 12207 and serve as a framework for process assessment and improvement in contexts where software is developed and evolved as a product and at the same time is part of an overall software-intensive system product.