About the cover: Cover is based on a maximum intensity projection of confocal images showing a luminal view of an airway in a precision-cut live mouse lung slice stained with 4-Di-2-ASP and loaded with Fluo-4. The cluster of small reddish cells in the center represents a pulmonary neuroepithelial body. For more information, see article by De Proost and colleagues, beginning on page 180.