This paper focuses on the improvement of radar reliability for automated highway vehicle applications. In particular, we address the topics of radar health monitoring and improved target tracking. Radar health monitoring poses a special challenge because a radar measures the distance to target vehicles whose motion is unknown in the absence of inter-vehicle communication. Traditional observer-based methods therefore cannot be used for the health monitoring task. A number of new approaches are summarized in this paper, including the use of a geographic database of known roadside targets, the detection of abrupt failures during target tracking and the use of a cheap redundant sensor. The use of a cheap redundant sensor is shown to be extremely valuable in the radar health monitoring task. The paper develops a new adaptive tracking algorithm to achieve good target tracking with a poor resolution sensor. An additional important problem addressed in the paper is that of tracking multiple targets which have crossing maneuvers. The paper proposes a new algorithm for tracking of multiple targets in which symmetric measurements are combined together with acceleration estimation so as to improve the stability properties of the existing Symmetric Measurement Equations (SME) technique for multiple target tracking.