This chapter is concerned with some of the factors affecting the export performance of firms in a limited number of industries during the period 1958-66. It places the authors work in its macroeconomic context by presenting a brief review of the UK balance of payments position and some of the hypotheses which have been suggested as explanations of the economy's export performance. In the post-war period, the United Kingdom (UK) has experienced a series of balance of payments crises, with their consequent implications for the foreign exchange price of sterling, the gold and dollar reserves and the pressure of domestic demand. The pressure of domestic demand is considered in relation to short-run variations around the long-run declining trend value of the UK's share in world trade. As a short-run explanation of the UK's export performance, the pressure of domestic demand can be analysed in terms of price, income and export allocative effects.