This case is intended to be used in conjunction with Rebar Steel Limited - Background Information, which gives common background information for each of the four cases: Rebar Steel Limited (A), Rebar Steel Limited (B), Rebar Steel Limited (C), and Rebar Steel Limited (D). In the (B) case, about five months after starting up the melt shop, the plant manager faces another problem: he is trying to decide whether to extend the mould line again. Improvements in process yield had slowed apparently because of slow downs in reconditioning moulds. Performance had improved when the mould line had been extended previously. Would another extension do the same?