The aim of the project reported here was to develop an efficient means of converting coal to acetylene, with a view to using the acetylene for a New Zealand -based plastics industry. When the project was begun in 1967 coal was the only feasible indigenous raw material. An economic survey was carried out on the manufacture of acetylene and its competitor ethylene in well industrialised countries in order to determine suitable economic criteria. A more intensive study was made of the possibilities of Polyvinylchloride manufacture in New Zealand, using ethylene from imported naphtha or acetylene from coal and lime via the carbide process.