Niche market steel producers tend to manufacture a wide range of products that are sold in low quantities. Current steelmaking—continuous casting (SCC) technology forces producers to operate according to combined make–to–stock/make–to–order order policies and keep in–process inventory. This leads to intermediate cooling of workpieces, high energy consumption, and high inventory and reheating costs. This paper evaluates links between product range and process flexibility upstream and downstream form the customer order decoupling point. The operational capabilities that result from improved process flexibility make diversified low cost steel production possible. At the same time the environmental sustainability of production can be improved. The strategic importance of process flexibility improvements are discussed with reference to the concept of competitive frontiers.