Vehicles are nowadays increasingly software-intensive.Current practice shows that the whole software system is tested, validated and then uploaded in ECUs in a monolithic fashion, before a vehicle is put in operation. Yet, adding speci c features or updates without restarting the full validation and upload procedure could yield to signi cant gains. Unfortunately, the AUTOSAR (AUTomotive Open System ARchitec- ture) standard does not include native support for software updates. In this paper, we de ne a set of new concepts in order to support dynamic software updates for automotive systems, and present mechanisms that implement these concepts within AUTOSAR.