This paper studies models of computation, software techniques, and analytical models for distributed timed systems. By "timed systems" we mean those where timeliness is an essential part of the behavior. By "distributed systems" we mean computational systems that are interconnected on a network. Applications of timed distributed systems include industrial automation, distributed immersive environments, advanced instrumentation systems, networked control systems, and many modern embedded software systems that integrate networking. The introduction of network time protocols such as NTP (at a coarse granularity) and IEEE 1588 (at a fine granularity) makes possible time coherence that has not traditionally been part of the computational models in networked systems. The main question we address in this paper is: Given time synchronization with some known precision, how does this change how distributed applications are designed and developed? A second question we address is: How can time synchronization help with realizing coordinated real-time events.