This book examines the relationship between the policies of the British state and its financial interests on the one hand, and on the other, the emerging economic policies and politics of Spain during the interwar years. Its aim is to highlight the effect on relations between the two countries of the two largest British investments in Spain of the period, Rio Tinto and the Consolidated Mining and Investment Corporation. The main proposition is that the interplay of these relationships had a significant impact on attitudes that shaped Anglo-Spanish relations throughout the 1920s and 30s. These attitudes in turn were an important factor in the failure of the trade agreement talks in 1935, which crystallised many of the changes in the relationship during the interwar years. More devastatingly, these same attitudes were to contribute, in the following year, to one of the most important political decisions of the period, the British Government's abandonment of Spain with its immediate and whole-hearted embrace of a policy of non-intervention following the military uprising of July 1936.