Previous studies have successfully differentiated human pluripotent stem cells into several neuronal subtypes, but no effort has been able to generate cortical interneurons, which are involved in neuropsychiatric diseases such as schizophrenia and autism. Lorenz Studer, Stewart Anderson and colleagues (Cell Stem Cell 12, 559–572, 2013) now report a method for deriving human cortical interneurons from a human embryonic stem cell line. The authors first identified conditions that would generate NKX2.1+ forebrain progenitors and tested whether these putative interneuron precursors showed the typical migratory potential seen in primary interneurons in mice. Indeed, they identified conditions in which robust migration of these cells occurred in the neocortex in mice. The authors then plated these cells over feeder cultures of mouse cortical pyramidal neurons and glia and compared them to cells grown on feeder cultures enriched for human cortical projection neurons. They found a consistent difference between NKX2.1+ cells plated on mouse and human cortical feeders, suggesting that the maturation of NKX2.1+ progenitors depends on local cellular context. Future work should investigate the functional mechanisms that determine species-specific maturation rates. The authors also suggest that studies involving transplantation of these derived interneurons into mouse models of neurological disease should be explored.