When the recurrence intervals of large earthquakes span several thousands of years, the dating of fault movements over long time intervals is essential for estimating the next event. Constraining the age of faulting, earthquake recurrence, or toppled rocks is especially important for determining if a fault is likely to break again soon. In recent years, cosmogenic nuclides have provided new insights into the dating of these ground movements. Approaches to gathering this information can be direct, such as dating fault surfaces with 36Cl, or indirect, such as dating fault-offset alluvial fans with 10Be or 26Al. New results from these methods are certain to better define the tectonic and seismic hazards in areas with increasing population density.