A patient interface (6000, 7000, 16000) for sealed delivery of a flow of air at a continuously positive pressure with respect to ambient air pressure to an entrance to a patient's airways including at least entrance of a patient's nares, wherein the patient interface is configured to maintain a therapy pressure in a range of about 4 cmH2O to about 30 cmH2O above ambient air pressure in use, throughout a patient's respiratory cycle, while the patient is sleeping, to ameliorate sleep disordered breathing; said patient interface comprising: a frame assembly (6100, 7100, 16100) including a shroud (6110, 7110, 16110, 17110) and connectors (6130; 6150, 7130) provided to the shroud, the connectors operatively attachable to headgear (6800, 7800, 16800); a cushion assembly (6175, 7175, 16175) provided to the frame assembly, the cushion assembly including a shell (6180, 7180, 16180) and a seal-forming structure (6200, 7200, 16200) provided to the shell and structured to form a seal with a patient's nose and/or mouth, the shell and the seal-forming structure cooperating to form a plenum chamber (6500, 7500, 16500) pressurizable to the therapy pressure, and the shell includes an inlet opening (6305, 16305) structured to receive the flow or air at the therapy pressure for breathing by the patient; and an air delivery connector (6600, 7600, 8600, 9600, 16600) provided to the frame assembly, the air delivery connector operatively connected to an air delivery tube for supplying the flow of air at the therapy pressure along an air flow path to the plenum chamber, wherein the cushion assembly is structured to releasably connect to the frame assembly independently of the air delivery connector, wherein the shell of the cushion assembly and the shroud of the frame assembly each comprise a relatively hard material that is more rigid than the seal-forming structure such that engagement between the shell and the shroud provides a hard-to-hard connection, wherein the air delivery connector is structured to releasably connect to the frame assembly independently of the cushion assembly, wherein a first seal for the air flow path is formed between the air delivery connector and the frame assembly, and a separate second seal is formed between the frame assembly and the cushion assembly, and wherein the first seal comprises a dynamic diametric seal and a dynamic face seal, and the second seal comprises a static diametric seal and a static face seal. a frame assembly (6100, 7100, 16100) including a shroud (6110, 7110, 16110, 17110) and connectors (6130; 6150, 7130) provided to the shroud, the connectors operatively attachable to headgear (6800, 7800, 16800); a cushion assembly (6175, 7175, 16175) provided to the frame assembly, the cushion assembly including a shell (6180, 7180, 16180) and a seal-forming structure (6200, 7200, 16200) provided to the shell and structured to form a seal with a patient's nose and/or mouth, the shell and the seal-forming structure cooperating to form a plenum chamber (6500, 7500, 16500) pressurizable to the therapy pressure, and the shell includes an inlet opening (6305, 16305) structured to receive the flow or air at the therapy pressure for breathing by the patient; and an air delivery connector (6600, 7600, 8600, 9600, 16600) provided to the frame assembly, the air delivery connector operatively connected to an air delivery tube for supplying the flow of air at the therapy pressure along an air flow path to the plenum chamber, wherein the cushion assembly is structured to releasably connect to the frame assembly independently of the air delivery connector, wherein the shell of the cushion assembly and the shroud of the frame assembly each comprise a relatively hard material that is more rigid than the seal-forming structure such that engagement between the shell and the shroud provides a hard-to-hard connection, wherein the air delivery connector is structured to releasably connect to the frame assembly independently of the cushion assembly, wherein a first seal for the air flow path is formed between the air delivery connector and the frame assembly, and a separate second seal is formed between the frame assembly and the cushion assembly, and wherein the first seal comprises a dynamic diametric seal and a dynamic face seal, and the second seal comprises a static diametric seal and a static face seal.