Composite repairs have been increasingly applied for maintenance and rehabilitation of piping, pipelines and vessels in the oil and gas industry, thus there is a growing need to monitor their in-service integrity, repair lifetime extension and prevent loss of containment of the product. There are many challenges of inspecting composite repairs including accessibility, inhomogeneous and anisotropic structure of composites, probability of detection, lack of adequate standards and diversity of composite materials amongst others. The current practice for inspection and monitoring of composites repair on oil and gas piping and pipelines is usually conducted based on International Standards Organisation (ISO) 24817 whereby visual inspection is generally performed to observe any irregularities on the surface like discolouration, cracks, chalking and blistering. This will usually be followed through with a coin tap test and Barcol hardness testing. Upon any findings of anomalies, further investigation is then performed using advance non-destructive testing (NDT) inspection technique to determine the integrity of the wrap, depending on the type and severity of defects. ISO 24817 has stated the general techniques that can be used to inspect the composites overwrap repairs including Ultrasound Technique, Radiography and Acoustic Emission. However, Petroliam Nasional Berhad (PETRONAS) has performed a series of assessments on various inspection techniques to seek suitable inspection methods for the composite wrap system, composites/substrate interface and/ or substrate. A total of 10 NDT techniques had been evaluated thus far including Laser Shearography, X-Ray, Microwave technique, Dynamic Response Spectroscopy (DRS), Acoustic Emission (AE), Computed Radiography (CRT), Pulse Eddy Current, Metal Magnetic Memory (MMM). This research summarises an overview of the effectiveness of the evaluated techniques and findings of the evaluation.