A quantitative geodynamic model for overthrusting of a passive continental margin during attempted continental subduction demonstrates the mechanical and thermal coupling between overthrust loads, the lithosphere, and the associated foreland basin. The model treats the lithosphere as a two-dimensional nonuniform elastic plate whose strength is controlled thermally. The thermal and flexural evolution of a margin is followed from initial rifting and passive-margin development, through overthrusting and foreland-basin deposition, to postdeformational erosion. Our models indicate the following. (1) Foreland-basin geometry is relatively insensitive to the age of the preexisting passive margin prior to overthrusting. Sensitivity decreases the farther the overthrust load is empl ced onto the craton. (2) Foreland-basin depth is strongly influenced by the size of the overthrust load. Maximum depths in excess of 10 km (6 mi) can occur given overthrust topography similar to the present-day Himalayas. (3) A few tens of kilometers of postdeformational erosion can occur across topographically high orogenic belts before moderate topography is attained. Very little of this eroded material is deposited in the foreland basin; most must bypass the basin because it also is subjected to erosion and associated flexural uplift. (4) Thick overthrusts, as interpreted from COCORP profiling, are consistent with low topographic expression because they were emplaced on preexisting oceanic and stretched continental lithosphere.