We study the effects of trade barriers and the persistence of past linkages on trade flows in the former Soviet Union (FSU). Estimating a gravity equation on 1987-1996 trade among and between nine Russian regions and fourteen FSU republics, we find that Russian regions traded 60 percent more with each other than with republics in the reform period (1994-1996). In contrast, they did not trade significantly more with each other than with republics in the pre-reform period (1987-90). Our results suggest that the bias towards domestic trade in the reform period is primarily a result of tariffs. We also find that past linkages, such as infrastructure, production and consumption chains, and business networks, have limited the reorientation of trade.