We present a new wheel slip controller and validate it both experimentally and in simulation. The control strategy is based on both wheel slip and wheel acceleration regulation, and ensures global asymptotic stability in closed loop. The stability analysis is established using tools for cascaded systems. This approach has the advantage of setting conditions on the control gains that are considerably milder, if compared with those obtained from Lyapunov's direct method. Simulations are provided to illustrate the robustness against vertical load variations and uncertainties in tyre-road friction. Furthermore, tests on a tyre-in-the-loop facility show that with our control law the wheel slip converges precisely to the assigned reference.