A surgical access device comprises a seal assembly (51) having a plurality of part circular sealing members (55) each attached to a common ring (53) which is held within the device about its longitudinal axis. In use, the sealing members are located radially inwards of the ring in a stacked relationship. When not within the device, the sealing members are movable from a position radially outwards of the ring to a position radially inwards of the ring. A seal core comprises the seal assembly and a protective member which, in use, is located on the proximal side of the seal assembly. A method of assembling the surgical access device is also provided.