While the 1906 earthquake marked a seminal event in the history of California, it can also be remembered as the birth of modern earthquake science in the United States. It was the first time that an earthquake was recognized and documented as the result of a recurring tectonic process of strain accumulation and release. Under the leadership of Professor Andrew Lawson, of the University of California (UC)–Berkeley, teams of scientists and engineers spread across the state, carefully collecting and documenting physical phenomena related to the quake. Their exhaustive data and thoughtful conclusions, published in landmark volumes two and four years after the earthquake, together with a complementary report published by the U.S. Geological Survey (USGS) in 1907, led to a number of new discoveries about the cause and effects of earthquakes. These discoveries underlie much of modern seismic hazard analysis.