Since Artificial Intelligence (AI) applications became mature, there has been growing interest in employing them into complex real equipment, especially in order to implement “Cyber-Physical Systems” (CPS). Since its dawn as a discipline, AI focused on simulating and reproducing human-like mental processes using formal structures, chasing the high-quality of reasoning. However, with the challenges posed by CPS, AI needs to take into account concrete real “timing performances” in addition to abstract reasoning about “time”. The AI definition of “intelligent agent” seems to perfectly apply to CPS. Nevertheless, to be real, intelligent agents need to deal with, reason about and act in time. This paper motivates such needs by deriving the roots of the definition of Real-Time Agent in Philosophy, Control Theory, and AI. Moreover, some examples are provided to demonstrate why RealTime agents are required in the “real world” of CPS. The paper concludes listing the desiderata of Real-Time Agents, wishing for the convergence of Multi-Agents Systems and RealTime Systems.