Since the beginning of automated driving, researchers and automakers have embraced the idea of completely removing the driver from the Dynamic Driving Task (DDT). However, the technology is not mature enough yet, additionally social and legal acceptance issues currently represent a major impediment for reaching the commercial stage. In this sense, the European Commission has focused attention on the approach of human-centered design for the new driver role in highly automated vehicles, evaluating a safe, smooth, progressive, and reliable collaboration between driver and automation, in both authority transitions and fluid collaborative control (or Shared Control). In particular, the HADRIAN (Holistic Approach for Driver Role Integration and Automation Allocation for European Mobility Needs) project is facing this challenge. The major contribution of this work is a general framework that allows di erent task-collaboration between driver and automation, such as shared and traded control, considering the status of the different driving agents: driver, automation, and environment. This integration will be evaluated under the framework of fluid interfaces which represent the basic needs for achieving a safe and effective human-machine interaction in automated driving. Also, the needs and challenges of the implementation are presented to achieve a fluid interaction.