The rapid manufacture of complex three-dimensional micro-scale components has eluded researchers for decades. Several additive manufacturing options have been limited by either speed or the ability to fabricate true three-dimensional structures. Projection micro-stereolithography (PμSL) is a low cost, high throughput additive fabrication technique capable of generating three-dimensional microstructures in a bottom-up, layer by layer fashion. The PμSL system is reliable and capable of manufacturing a variety of highly complex, three-dimensional structures from micro- to meso-scales with micro-scale architecture and submicron precision. Our PμSL system utilizes a reconfigurable digital mask and a 395 nm light-emitting diode (LED) array to polymerize a liquid monomer in a layer-by-layer manufacturing process. This paper discusses the critical process parameters that influence polymerization depth and structure quality. Experimental characterization and performance of the LED-based PμSL system for fabricating highly complex three-dimensional structures for a large range of applications is presented.