This paper examines the impact of liberalizing the telecommunications services sector on investment and output in the Asia-Pacific Economic Cooperation (APEC) countries by estimating a system of four structural equations that takes into account the causal relationship between national income and telecommunications infrastructure. The degree of openness to trade in telecommunications is represented by a carefully constructed index that reflects a country鈥檚 trade and investment policy in terms of market access, national treatment and regulatory principles. One interesting finding from the empirical analysis is that the effects of trade liberalization depend on the risk rating of a country. In countries with relatively high risk ratings liberalization reduces investment in telecommunications.