The use of composite materials has increased substantially over the last few decades, led by a demand to reduce weight from the aerospace industry. While composite manufacturing can reduce the need for joining parts, some joints are still needed and mechanical fastening is the most widely used method to do so. Mechanical fastening relies on drilling holes in the parent material, which has the potential to create defects. Drilling of fibre-reinforced composites is a complex process differs significantly from the machining of conventional metals due to their anisotropic, inhomogeneous and highly abrasive characteristics. The abrasive nature of composite materials can quickly degrade tools, resulting in lower quality drilling. Detection and monitoring of tool wear as well as the use of Non-Destructive Testing (NDT) to ensure the integrity of joints is clearly an important topic in composite manufacturing.