Abstract: The conformal infinity of a quaternionic-Kähler metric is a codimension-3 distribution called quaternionic contact. In dimension greater than 7, a quaternionic contact structure is always the conformal infinity of a quaternionic-Kähler metric. On the contrary, in dimension 7, we prove a criterion for quaternionic contact structures to be the conformal infinity of a quaternionic-Kähler metric.