This manuscript introduces the design of a controller that ensures predefined-time convergence for a class of second-order systems. In contrast to finite- and fixed-time controllers, predefined-time schemes allow to prescribe a bound for the convergence time as a control parameter. First, a predefined-time integral sliding mode controller allows rejecting unknown but bounded matched disturbances. Then, the system dynamics evolve free of the effect of disturbances during the integral sliding motion. Finally, an ideal controller enforces convergence also in predefined-time. A Lyapunov-like characterisation for predefined-time stability is conducted, and numerical results are provided to illustrate the validity of the proposed technique.