We describe two different approaches to the problem of decoupling ions in polymer electrolytes from the chain segmental motions in order to obtain high conductivities even close to the glass transition temperature. In one of the two, the ions are also decoupled from each other so that single ion conducting materials can be obtained. The first method involves the use of polymeric anions while the second uses side-chain secondary relaxation as the principle behind the fast motion. Neither principle is new but the performance seems to be quite good in the cases described. (C) 2000 Elsevier Science Ltd. All rights reserved.