A suspension liner sleeve providing an interface between a residual limb and a hard prosthetic socket includes a resilient seal element extending around its outer periphery to enhance a sealing effect between the sleeve and the interior of a prosthetic socket to isolate the distal end of the socket from atmosphere after the sleeve with a residual limb has been inserted within the socket and to thereby improve the retention of the liner sleeve and the residual limb in the prosthetic socket.