The Magnetic Barkhausen Noise (MBN) technique is considered as a potential Non-Destructive Evaluation (NDE) method for assessing material properties in case-hardened gears. For gear manufacturing industries, the evaluation of material properties such as tempering induced changes in hardness level and the associated microstuctural changes, variations in case-depth of hardened layer, grinding process induced alteration in microstructure, hardness and residual stress distributions are of primary importance in order to ensure the quality of gears. During the service life of gears, the evaluation of the contact fatigue damage and the assessment of remaining quality life of gears are important in order to prevent catastrophic failures. This paper presents an overview of different research and developmental studies carried out at Design Unit, Newcastle University on the MBN technique suitable for different applications in the evaluation of quality of gears.