An interfacing structure for a mask system includes a cushion component adapted to contact the patient's face in use and a cushion-to-frame component provided to the cushion component. The cushion-to-frame component is structured to secure the cushion component to a mask frame of the mask system. The cushion-to-frame component includes a cushion side adapted to interface with the cushion component and a frame side adapted to interface with the mask frame. The cushion side includes a platform to engage and support the cushion component. The platform provides an engagement surface to engage the cushion component and inner and outer flanges provided to opposing ends of the platform to guide, support and/or retain the cushion component on the platform.