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A velocity (Vs) and structure model is derived for the Los Angeles Basin, California based on ambient-noise surface wave and receiver-function analysis, using data from a low-cost, short-duration, dense broad-band survey (LASSIE) deployed across the basin. The shear wave velocities show lateral variations at the Compton-Los Alamitos and the Whittier Faults. The basement beneath the Puente Hills-San Gabriel Valley shows an unusually high velocity (similar to 4.0 km s(-1)) and indicates the presence of schist. The structure of the model shows that the basin is a maximum of 8 km deep along the profile and that the Moho rises to a depth of 17 km under the basin. The basin has a stretch factor of 2.6 in the centre grading to 1.3 at the edges and is in approximate isostatic equilibrium.