Book excerpt: This review discusses the preparation of highly ordered polyacetylene blends and compares forms of polyacetylene obtained by different methodsand includes an analysis of the formation of defects in polyacetylene during growth of the polyene chain and cis-trans isomerisation. The mechanism of acetylene polymerisation with rhenium catalysts, and the reactivity of highly ordered polyacetylene blends to oxidation and doping are also discussed. An additional indexed section containing several hundred abstracts from the Rapra Polymer Library database gives useful references for further reading.