Optimal Taxation of International Income Flows *

Double taxation of international income flows has been regarded as undesirable and international tax agreements have been negotiated to avoid it. The questions asked are whether double taxation is appropriate and whether cooperation is required to reach the optimal solution. The results are that generally some double taxation is desirable, as long as taxes are applied at the appropriate rates, and that an efficient solution can be attained in the absence of explicit cooperation using a deduction rule, instead of the now commonly used credit rule. A rationale for the current system of tax agreements and their emphasis of the credit rule is discussed.