This paper deskribes the value of the Surface Curvature Index (SCI) as a structural indicator in the design of flexible overlays on cracked road pavement. The SCI can easily be drived from falling weight deflection measurements and represents the difference between the centre deflection at a certain distance from the load. Based on fracture mechanics principles and finite element calculations, it is demonstrated that the SCI can be used in evaluating pavement structures for flexible overlays on cracked road pavements. The SCI can be used in evaluating pavement structures for reflective crack potential.