Making perfect atomic arrays Arrays of atoms can be a useful resource for quantum information. However, loading atoms into arrays is typically a stochastic process, which leads to imperfections. Two groups have now performed defect-free assembly of atoms into arrays (see the Perspective by Regal). The researchers first loaded the atoms stochastically and imaged the system. They then shuttled the atoms around to form perfect arrays. Barredo et al. worked with two-dimensional arrays, creating a variety of spatial configurations. Endres et al. manipulated atoms along a line. By further cooling down the atoms and generating interactions among them, the techniques may also find use in quantum simulation. Science , this issue p. 972 , p. 1021 ; see also p. 1024