Seat for motor vehicles, the back rest of which seat comprises a supporting structure, a padding arranged thereon and a cover arranged over the latter, wherein - the padding leaves a receiving space free, - an airbag device is arranged in the receiving space in order, in the event of triggering, to deploy an airbag into a region located laterally next to the occupant, - the cover has a tear seam which is designed for the exit of the airbag, - a respective planar reinforcing material layer (15a, 15b) which is located between padding and cover is attached by a respective first edge region (16a, 16b) to the tear seam on both sides in order to introduce the forces, which are required for the tearing-open, into the tearing seam, - and the two reinforcing material layers (15a, 15b) are connected at a respective second edge region (17a, 17c), which is situated opposite the respective first edge region (16a, 16b), via a number of fixing means in such a manner that a bag-shaped fixation enclosing the bag is formed, characterized in that the receiving space is designed so as to be open towards an outer side surface of the back rest, the fixing means are fastened to the back rest and are joined together with or are connected to the padding, and wherein the fixing means comprise a wire with a plurality of straight sections and protruding eyelets located in between, and wherein the second edge region of the first reinforcing material layer is connected to a holding strip into which eyelets are introduced in a spaced-apart manner, and wherein the second edge of the second reinforcing material layer is serrated and thereby forms a number of preferably tapering attachment tabs, and wherein the holding strip of the first reinforcing material layer is connected to the straight sections of the fixing means via rigid tension means, and the attachment tabs are connected to the sections with eyelets of the fixing means via rigid tension means. - the padding leaves a receiving space free, - an airbag device is arranged in the receiving space in order, in the event of triggering, to deploy an airbag into a region located laterally next to the occupant, - the cover has a tear seam which is designed for the exit of the airbag, - a respective planar reinforcing material layer (15a, 15b) which is located between padding and cover is attached by a respective first edge region (16a, 16b) to the tear seam on both sides in order to introduce the forces, which are required for the tearing-open, into the tearing seam, - and the two reinforcing material layers (15a, 15b) are connected at a respective second edge region (17a, 17c), which is situated opposite the respective first edge region (16a, 16b), via a number of fixing means in such a manner that a bag-shaped fixation enclosing the bag is formed, characterized in that the receiving space is designed so as to be open towards an outer side surface of the back rest, the fixing means are fastened to the back rest and are joined together with or are connected to the padding, and wherein the fixing means comprise a wire with a plurality of straight sections and protruding eyelets located in between, and wherein the second edge region of the first reinforcing material layer is connected to a holding strip into which eyelets are introduced in a spaced-apart manner, and wherein the second edge of the second reinforcing material layer is serrated and thereby forms a number of preferably tapering attachment tabs, and wherein the holding strip of the first reinforcing material layer is connected to the straight sections of the fixing means via rigid tension means, and the attachment tabs are connected to the sections with eyelets of the fixing means via rigid tension means.