<p>Surface extravehicular activity (EVA) is one of the most cognitively demanding actions that astronauts can execute. Decrements in cognitive performance present an important risk to crew safety, yet there is currently insufficient data to characterize the cognitive capabilities required for optimal surface EVA performance. Here, we conducted a cognitive task analysis with 15 astronauts and subject matter experts to characterize the cognitive demands of surface EVA tasks and to identify the risks associated with decrements in cognitive performance during surface EVA. The information gathered from this study identifies the specific cognitive capabilities that astronauts will need for future surface EVA and provides the foundation for (1) prioritized and targeted cognitive performance measurement, (2) EVA simulation design at varying levels of cognitive workload, and (3) the development of technologies that can inform NASA standards and guidelines and EVA planning for future exploration class missions.</p>