While there have been significant discussions in various international forums regarding revenue characterization and the creation of a permanent establishment in the e-commerce environment, the questions of the impact of domestic source rules and transfer pricing principles on e-commerce transactions have not been as thoroughly explored. The application of source rules can have substantial consequences on whether a transaction is subject to local tax, but in many circumstances the novel business models produced by e-commerce transactions may make a determination of source of income problematic. Similarly, application of existing transfer pricing rules may be made more difficult as different business models emerge in the new economy. The difficulties in applying both sets of rules have inspired policy debates concerning how best to apply existing principles to e-commerce transactions. Subject I of the 2001 Congress explores these topics.