Over the years, the World Bank's structural adjustment programmes have been criticized on the grounds that they have adverse effects on the living standards of the people in developing countries. The main objective of this article is to test the hypothesis that the adjustment lending countries have had a superior (or inferior) performance to the non-adjustment lending countries during the 1980s. A new dummy variable regression model is used to test this hypothesis. The model controls for initial conditions, external shocks and other exogenous variables which affect different countries differently. The standard of living is measured by several socioeconomic variables including per capita income, lifeexpectancy at birth, infant mortality rate, and literacy rate.