A central proposition of international trade theory is that trade allows a country to achieve a higher level of income than would otherwise be possible. Initial studies have shown evidence in support of a positive relationship between the volume of trade and the level of national income. However, numerous problems have prevented the estimation of a consistent relationship between trade and income. These problems include endogeneity, cointegration between trade and income, and the lack of an accurate measure of trade openness. This study investigates the relationship between trade and income in three distinct ways. First, the endogenous nature of trade in a simple growth equation is controlled for by constructing a predicted level of trade from a gravity model. The results show that greater trade does exert a positive influence on economic growth; however, once the effects of geography are controlled for in the growth equation the effect of trade becomes insignificant. Second, trade is included in a neoclassical production function to assess the dynamic and causal relationships that exist among exports, imports, and national income. The variables are first tested for the presence of unit roots and the possibility of cointegration. Subsequently, appropriate Granger causality tests are used to determine the causal patterns among the variables of the model. The results of the Granger causality tests indicate that both exports and imports are important determinants of national income for several of the countries examined in the study. Finally, the actual trade shares and the predicted trade shares from a large sample of countries are used to construct a new trade restrictiveness statistic. A higher value of the statistic indicates that a country has adopted more restrictive trade policies. The trade restrictiveness measure is included in a growth equation to assess the effects that trade policy has on the average annual growth rate of per capita income. The results of the estimation indicate that countries that began the sample period with more restrictive trade policies tended to grow at a faster rate than countries with less restrictive trade policies; however, the relationship is statistically insignificant.