There is growing interest in life extensions to enable longer term operation (LTO) for both existing nuclear power plants (NPPs) and proposed new NPPs. In order to justify an initial license extension for the 40–60 yr period, new nondestructive examination (NDE) approaches have been developed and deployed by NPP operators in their aging management programs. However, to achieve the goals of even longer term operation, and specifically for the United States in looking at methodologies to support subsequent license renewal periods (i.e., 60–80 yr and beyond), it is necessary to understand the capabilities of current NDE methods to detect, monitor, and trend degradation and hence enable timely implementation of appropriate mitigation and corrective actions. This paper discusses insights from past experience, the state-of-the-art, and current activities in the move toward providing a capacity for proactive management of materials degradation to support NPP LTO.