The continuous increase in digital system complexity is raising the area cost of redundancy-based fault and defect tolerance. This paper introduces a technique for heterogeneous redundancy in control path and datapath circuitry that provides high reliability with area overhead that is independent of system complexity. Small amounts of circuit-specific reconfigurable logic are finely integrated with fixed-logic circuitry to provide fine-grained heterogeneous fault and defect tolerance. Results reveal that the technique is effective for a variety of circuits, providing high reliability with a constant magnitude area overhead that is independent of system complexity.