The Yugoslav external sector has undergone vast changes, in value and composition, during the first two decades in which the system of workers' self-management has been operative. This paper examines the growth and structural change of foreign trade at various levels of aggregation. While imports are examined to some extent, the major concern is with exports. To provide a general perspective of the changes that have occurred, the current account of the balance of payments is examined in the following section. This is followed by an analysis of structural change at the one-digit SITC level and in terms of the Yugoslav broad classifications of exports and imports according to end use and stage of production. Structural change at this level of aggregation has been more pronounced in the export sector than has been the case with imports. The manufactured export share of total exports has grown rapidly, as have the shares of capital goods exports and exports of more highly-processed goods. Imports of manufactured goods have also grown more rapidly than primary goods imports. Supply bottlenecks have stimulated imports of the intermediate goods, especially in the latter half of the period.