Previous alliancing research has seldom addressed the implication of transaction costs and the impact of transaction attributes on transaction costs in project alliancing. Using multiple regression analysis on a sample of Australian alliances, this study tests the differential impact of uncertainty, frequency, and various dimensions of contracting parties' asset specificity on three individual transaction cost elements (set-up, monitoring, and enforcement costs). The results indicate that the impact of transaction attributes on transaction costs varies. Uncertainty has a positive impact on all three transaction cost elements. Frequency and some dimensions of contracting parties' asset specificity are positively associated with set-up costs and monitoring costs, which, however, does not apply to enforcement costs. The findings provide empirical evidence in support of the transaction cost economics' prediction regarding the influence of transaction attributes on transaction costs in the Australian construction industry, and thereby add another perspective to the knowledge base in the construction management discipline. The measurement methods of transaction attributes and transaction costs presented have valuable implications for future research.