In this letter, a method of generating spatially defined electrospun microarchitectures by direct photolithographic patterning of electrospun Films is described, A photoinitiator, benzoin methyl ether, is incorporated into a solid thermoplastic electrospun polyurethane matrix selectively photo-cross-linked by standard photolithographic methods. Subsequent development in in organic solvent yields spatially defined electrospun microstructures oil a single substrate. Utilizing a multilayer approach, the method allows for the assembly of complex hierarchical electrospun structures on single substrates using methods analogous to the conventional microfabrication of solid-state devices.