A cushion (2040) for providing a sealed interface between a face and a frame of a respiratory mask system for delivery of a supply of air at positive pressure to the entrance of the airways of a person is disclosed. One factor in the efficacy of therapy and compliance of patients with therapy is the comfort and fit of the cushion. In one form the cushion includes a stabilising portion (2520) constructed and arranged to provide stability to a masks system in lateral direction, and/or in the in-and-out of a plane of the face direction to improve comfort and fit. The cushion has a seal including a nasal bridge portion adapted to form a seal on a nasal bridge of the person and at least one lateral stabilising portion adapted to provide a force on a side of a nose in the region of the nasal bridge, a corner of mouth region and a lower lip region. The cushion further comprises a wall portion located between a retention feature of the cushion and the sealing portion, the wall portion having a first cross-sectional profile in a corner of mouth region and a second cross-sectional profile in a side of nose region.
