VIVIANE BALADI and CARLANGELO LIVERANI EXPONENTIAL DECAY OF CORRELATIONS FOR PIECEWISE CONE HYPERBOLIC CONTACT FLOWS ABSTRACT We prove exponential decay of correlations for a realistic model of piecewise hyperbolic flows preserving a contact form, in dimension three. This is the first time exponential decay of correlations is proved for continuous-time dynamics with singularities on a manifold. Our proof combines the second author's version [28] of Dolgopyat's estimates for contact flows and the first author's work with Gouezel [5] on piecewise hyperbolic discrete-time dynamics.