In spite of an ever-growing supply of metals, actors have long feared metal shortages. This thesis – departing from an understanding that metals scarcity is not an objective geological fact, but an experience, a fear of a shortage – explores why business and state actors have experienced metals as scarce and how they coped with scarcity from 1870 to 2015. The underlying reasons for scarcity experiences originated in high prices, a lack of substitutes, domestic unavailability, limited infrastructure and increased demand. In the view of businesses and the state, a shortage of metals could hinder successful industrialization. Defining metals as scarce was a first step in their attempts to ensure access through exploration, recycling, substitution, and trade agreements. This dissertation presents five case studies which provide insights into three selected aspects of metals scarcity that have been overlooked in previous studies. First, while small countries experienced and coped with metals scarcity in a similar way to large nations, they were more vulnerable because of their dependence on transnational flows controlled by larger countries. Yet if they remained neutral in international conflicts, they could enjoy other opportunities to import resources than their larger rivals. Second, industries experienced metals scarcity before World War I; with the onset of the Second Industrial Revolution, at the very latest, new technologies were often dependent on metals which had never before been used commercially – there were not yet any extraction systems in place. However, once these metals began to circulate, state actors became aware of the international traffic and began to classify certain metals as critical. Thirdly, technological change has affected – and been affected by – metals scarcity. If a metal was scarce, manufacturers were likely to embark on a different path to production. Inversely, sometimes new technologies were able to alleviate perceptions of scarcity. / <p>QC 20171206</p>