Objective. Applying existing theories relating to investment risk, this article examines the effects of judicial strength and adherence to the rule of law on portfolio investment in the developing world. We aim to demonstrate that countries with higher levels of judicial strength and rule of law are more able to attract portfolio investment because they provide greater protection of property rights and a better risk environment for investors. Methods. Using time-series data for 79 developing countries for the period 1996-2005, we employ panel-corrected standard errors multivariate regressions to demonstrate that higher levels of judicial strength and rule of law are associated with higher levels of portfolio investment. Results. We find that a one standard deviation increase in overall judicial strength and rule of law results in more than a 50 percent increase in portfolio investment. In separate analyses, we show that a one standard deviation increase in specific measures of judicial independence, impartial courts, and protection of property rights leads to increases in portfolio investment ranging from 27 percent to 184 percent. Conclusion. Judicial strength and adherence to the rule of law are important determinants of portfolio investment in the developing world.