Non Destructive testing is an ideal approach for in-situ assessment of soils, subgrades and pavements. Portable Falling Weight Deflectometer and similar equipment such as German Dynamic Plate, Soil Stiffness gauge distinguished by load pulse rate and contact pressure are being widely used in stiffness determination. The stiffness modulus obtained through LWD & DCP testing on a flexible pavement and or by LWD & Schmidt's Hammer testing on a rigid pavement could be respectively correlated. Quality of field data establishes the reliability of the experiments. Such a correlation can be used to do away with the high cost of LWD and experience required to predict the required parameters for LWD using the results obtained from the other two devices.