eLife assessment
This is a valuable contribution to the effort to provide genetic access to and characterization of the major classes of interneurons in the mammalian neocortex. The authors develop an improved strategy for intersectionally targeting a fourth (and final) major category of diverse interneurons in the mouse, including the previously studied neurogliaform cells. They provide a detailed characterization of these cells and show convincingly that their genetic strategy can be used to identify and manipulate these cells, both in vitro and in vivo.