This Special Paper of the Geological Society of America contains 10 expanded papers (204 p.) that describe the state-of-the-art in paleoseismology as it existed in 2011. The first paper is an overview of paleoseismology by Audemard and Michetti, giving an international perspective and emphasizing the newly-formulated Environmental Seismic Intensity [ESI] scale of 2007. Following are nine case-history papers. From the USA, McCalpin et al. and Olig et al. describe fault trenching investigations in the Rio Grande rift of New Mexico. Next are four papers from South America, showing the evolution of methodologies there in the past decade. Lalinde et al. and Lopez & Audemard describe paleoseismic studies in Columbia; Audemard describes multiple-trench investigations in Venezuela; and Hermanns & Niedermann use lake sediment deformation and landsliding to reconstruct late Quaternary paleoearthquake sequences in Argentina. Beck describes how lake sediments in the Alps may contain archives of late Quaternary paleoearthquakes, and Clark et al. describe late Quaternary faulting in the intracratonic area of Tasmania. Ending the collection of papers is a modeling study by Biasi et al., explaining how the magnitude of paleoearthquakes might be derived from point measurements of surface displacement.