A theoretical analysis based on continuum elasticity and atomistic simulations is presented of the structural stability of the InAs/GaAs(110) interface during InAs epitaxy. A transition is predicted from a coherently strained system to one with a semicoherent interface consisting of a regular array of edge misfit dislocations at a critical film thickness h f , c of 6 monolayers (ML) for a GaAs compliant substrate of 10ML thickness. The theoretical results for h f , c , the coherently strained system, and the film surface profiles as a function of film thickness are in excellent agreement with recent experimental data.