Figure shows the trajectories of water droplets of different radii R = 0.019-1.3 mm and different initial U I = 3-40 cm s -1 impacting a Black Si superhydrophobic surface (See Supporting Videos S1-S3). Depending on the initial conditions, the water droplet can either rebound and lift completely off the surface (sometimes multiple times, see Figure ) or come immediately to a complete stop, i.e., no rebound (Fig. ). The energy loss in droplet after each rebound can be quantified by the restitution coefficient e = U R /U I and equivalently e n = ! h n /h n-1 where h n is the maximum droplet height after n th rebound (Figure ). In our experiments, we use both definitions to calculate e and both give similar values. In this paper, we will explain and propose scaling laws to account for the observed e values, which can vary from 0 (Fig. ) to approximately 1 (for rebound number n = 6-13 in Figure ). We start by comprehensively characterizing the wetting properties of the two superhydrophobic surfaces (Glaco and Black Si), in particular the static contact radius r s (and hence also the static contact angle θ), the maximum spreading radius r max , and the contact angle hysteresis ∆ cos θ which is equivalent to the non-dimensionalized friction force acting on a moving droplet, i.e., Furmidge's law. Static contact radius. For a sessile droplet making a contact angle θ, r s results from a balance between the droplet's weight 4/3 πR 3 ρg, the capillary adhesion force 2πr s γ sin θ, and the Laplace pressure (2γ/R)πr 2 s , i.e.,