Originally published in 1970. Input-output analysis has been described as the "lynch-pin of modern economic planning". Its purpose is to trace the consequences of any economic change through each sector of the economy; to measure, for example, the effects of an increase in fuel tax on the price of food, or of an expansion in car production on the country’s import bill. This kind of knowledge is clearly essential for making economic predictions. This book presents the proceedings of the 1968 Manchester Conference including six outline papers, each followed by discussion, and several summaries of ongoing and proposed research which were added afterwards. The speakers and participants constituted a representative sample of persons from Industry and Commerce, as well as the Universities and the Civil Service.