A method for multiple beam additive manufacturing of a three-dimensional structure formed by a plurality of build layers (408-1 to 408-7), the method comprising: providing an array of light sources (130, 230-1 to 230-n) and an array of optical fibers (132, 232-1 to 232-n) coupled to the array of light sources (130, 230-1 to 230-n), respectively, and an optical head (140, 240, 340, 440) including output ends of the optical fibers (132, 232-1 to 232-n); delivering powder layers of powder material on a powder bed support system that moves vertically and incrementally to accommodate each of the powder layers; and forming build layers (408-1 to 408-7) of the three-dimensional structure in each of the powder layers of powder material, wherein forming each of the build layers (408-1 to 408-7) includes performing multiple beam distributed exposures (131, 231-1 to 231-n) on different regions of each powder layer to selectively fuse corresponding regions of the powder material, wherein performing each of the multiple beam distributed exposures (131, 231-1 to 231-n) includes simultaneously generating light from selected light sources in the array of light sources (130, 230-1 to 230n) such that beams of light (131, 231-1 to 231-n, 331-1 to 331-n, 431) are emitted from the output ends (234-1 to 234-n) of the optical fibers (132, 232-1 to 232-n) coupled to the selected light sources and directed to the corresponding regions of each powder layer to form a distributed exposure pattern including spaced beam spots (233a, 233b, 233c) and performing the multiple beam distributed exposures (131, 231-1 to 231-n) on each of the powder layers includes scanning the optical head (140, 240, 340, 440) with an interleaved scan pattern across the powder layers, wherein the beams of light (131, 231-1 to 231-n, 331-1 to 331-n, 431) are directed with a power and duration sufficient to melt the powder material in the corresponding regions such that the powder material in the corresponding regions fuses to form fused regions, wherein the beam spots (233a, 233b, 233c) in each of the multiple beam distributed exposures (131, 231-1 to 231-n) are spaced sufficiently to separate the fused regions formed by each of the multiple beam distributed exposures (131, 231-1 to 231-n) and the spaced beam spots (233a, 233b, 233c) are interleaved in a non-contiguous array to fill spaces between the spaced beam spots (233a, 233b, 233c), wherein each of the fused regions corresponds to a voxel of the three-dimensional structure and wherein the fused regions of the powder material in each of the powder layers collectively form each of the respective build layers (408-1 to 408-7) of the three-dimensional structure. providing an array of light sources (130, 230-1 to 230-n) and an array of optical fibers (132, 232-1 to 232-n) coupled to the array of light sources (130, 230-1 to 230-n), respectively, and an optical head (140, 240, 340, 440) including output ends of the optical fibers (132, 232-1 to 232-n); delivering powder layers of powder material on a powder bed support system that moves vertically and incrementally to accommodate each of the powder layers; and forming build layers (408-1 to 408-7) of the three-dimensional structure in each of the powder layers of powder material, wherein forming each of the build layers (408-1 to 408-7) includes performing multiple beam distributed exposures (131, 231-1 to 231-n) on different regions of each powder layer to selectively fuse corresponding regions of the powder material, wherein performing each of the multiple beam distributed exposures (131, 231-1 to 231-n) includes simultaneously generating light from selected light sources in the array of light sources (130, 230-1 to 230n) such that beams of light (131, 231-1 to 231-n, 331-1 to 331-n, 431) are emitted from the output ends (234-1 to 234-n) of the optical fibers (132, 232-1 to 232-n) coupled to the selected light sources and directed to the corresponding regions of each powder layer to form a distributed exposure pattern including spaced beam spots (233a, 233b, 233c) and performing the multiple beam distributed exposures (131, 231-1 to 231-n) on each of the powder layers includes scanning the optical head (140, 240, 340, 440) with an interleaved scan pattern across the powder layers, wherein the beams of light (131, 231-1 to 231-n, 331-1 to 331-n, 431) are directed with a power and duration sufficient to melt the powder material in the corresponding regions such that the powder material in the corresponding regions fuses to form fused regions, wherein the beam spots (233a, 233b, 233c) in each of the multiple beam distributed exposures (131, 231-1 to 231-n) are spaced sufficiently to separate the fused regions formed by each of the multiple beam distributed exposures (131, 231-1 to 231-n) and the spaced beam spots (233a, 233b, 233c) are interleaved in a non-contiguous array to fill spaces between the spaced beam spots (233a, 233b, 233c), wherein each of the fused regions corresponds to a voxel of the three-dimensional structure and wherein the fused regions of the powder material in each of the powder layers collectively form each of the respective build layers (408-1 to 408-7) of the three-dimensional structure.