Cover picture: Extreme stretch growth of integrated axon tracts (middle) spanning two populations of neurons (top and bottom). Before the initiation of stretch growth, the two populations of neurons were adjacent, bridged by axons that were only~100 μm long. The bridging axons were progressively stretched using a microstepper motor system, resulting in a rapid expansion to 5 cm (shown here) and greater. Remarkably, axons can be stretch grown at rates of at least 8 mm per day while maintaining an intact cytoskeleton. For details, see the article by Pfister et al. in this issue (pages 7978–7983).