A growing interest in deformable electronics has fueled remarkable advancement in the area of conductive, stretchable composites suitable for use in electric circuits, interconnects and electrodes. This review provides a brief introduction as to the effect of conductive filler geometry on percolation and summarizes the design of the elastic conductive composites on the basis of five different methods: implanting conductive fillers in elastomers, filling microchannels with liquid metals, infiltrating elastomers in conductive-filler networks, blending conductive fillers with elastic polymers, and synthesizing metal fillers within elastomers. For each method, remarkable advances are described and the technological issues that require further improvement are presented, along with possible solutions. This review provides perspectives as to the application of conductive composite elastomers for deformable electronics and energy-related devices. (C) 2014 Elsevier Ltd. All rights reserved.