I will report on joint work with Alba Malaga Sabogal. In 1912 Paul et Tatyana Ehrenfest proposed the wind-tree model in order to interpret the ergodic hypothesis of Boltzmann. In the Ehrenfest wind-tree model, a point particle (the “wind”) moves freely on the plane and collides with the usual law of geometric optics with irregularly placed identical square scatterers (the “trees”). We show that for generic configurations (in the sense of Baire) the wind-tree model has very nice dynamics in a.e. direction: minimality, ergodicity, and infinite ergodic index.