A liner that covers an amputation stump and which cushions the stump when it is placed into a prosthesis socket includes selectively inflatable bladders for customizing the liner to fit individual patients. In a first embodiment, the liner is made of two liner parts, one being an inner liner and the other being an outer liner. The inner liner is placed onto the amputation stump and a prosthetist determines the region or regions where bladders are needed to provide a comfortable fit. The region or regions are outlined with an adhesive and the outer liner is then brought into overlying relation to the inner liner so that the two liner parts adhere to one another along the outlined regions. Upon inflation, the inner liner conforms to the shape of the amputation stump to provide enhanced cushioning and the outer liner conforms to the shape of the interior wall of the socket and the patient receives a custom fit from a simple appliance. An annular bladder at the proximal rim of the socket creates a substantially perfect seal to maintain the suction within the socket. In a second embodiment, a tubular cuff replaces the outer liner and a triple seal is achieved when the socket is inserted between the cuff and the inner liner. In a third embodiment, an annular return bend is formed in the inner liner so that the cuff is integral with it.