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Surfaces that are non-wetting to water, ie, superhydrophobic,[1–4] are of considerable interest for scientists and engineers, not only for fundamental research, but also for the numerous attractive features including self-cleaning and non-wetting fabrics,[5] anti-fogging,[6] anti-icing,[7] buoyancy [8] and drag reduction.[9] By definition, a surface is superhydrophobic if the contact angle between a water drop and the surface at the solid/liquid/air interface is larger than 150, and the contact angle hysteresis is small, ie, drops readily slide or roll off when the surface is tilted slightly.[10–12] Here we explore the feasibility of using superhydrophobicity for guided transport of water droplets. We demonstrate a simple yet efficient approach for droplet transport, in which the droplet is moving on a superhydrophobic surface, using gravity or electrostatic forces as the driving force for droplet transportation and using tracks with vertical walls as gravitational potential barriers to design trajectories. Although the slope of the platform is as small as a few degrees, the drops move at a considerable speed up to 14 cm s− 1, even in highly curved trajectories. We further demonstrate splitting of a droplet using a superhydrophobic knife and drop-size selection using superhydrophobic tracks. These concepts may find applications in droplet microfluidics and lab-on-a-chip systems where single droplets with potential analytes are manipulated.[13–16] There are two factors required for obtaining a superhydrophobic surface. First, the surface must have suitable roughness. Second, the surface must have a hydrophobic surface chemistry.[17, 18] If these requirements are fulfilled, a …