Small and medium-sized enterprises (SMEs) have been important for Vietnam's rapid economic development. This paper investigates the ways in which Vietnam's SMEs have been affected by the ongoing internationalization of the Vietnamese economy and points out the challenges that lie ahead if the country's plans for further trade liberalization are realized. The basis of our analysis is a unique database on the activities of a large sample of Vietnamese SMEs during 1990, 1996, and 2002, with quantitative data about company operations, as well as qualitative information about the entrepreneurs' perceptions of the current business environment and their expectations about the future.