Oriented crystal growth on an amorphous substrate has been achieved using an artificially created surface‐relief grating. Crystallites of KCl grown from a water solution onto a 320‐nm spatial‐period square‐wave grating in SiO2nucleated preferentially at vertical steps and grew with ⟨100⟩ directions parallel to the grating axis. It is proposed that artificially created surface microstructures may provide a new means of manipulating the growth and orientation of crystalline overlayers.