[en] This paper describes a new control system which has recently been designed and installed at the Advanced Test Reactor at INEL, replacing an older system that had been in service for some 17 years. Based on modern digital technology, the new system provides improved capability, reliability, and an enhanced man/machine interface that includes comprehensive failure and error messages and voice synthesis. In addition to control functions, and transparent to the operator, the system performs continual on-line checks to sense subsystem failures and takes appropriate automatic action. In the maintenance mode, service technicians can carry on a dialog with the controller to quickly identify faulty components. The operational capabilities of the new system are summarized, and reactor operator training, experience, and acceptance of the system are discussed