Three perspectives on the determinants of Japan's official development assistance (ODA) program are often represented as distinct, valid explanations of the aid program. Yet few studies have attempted to simultaneously test the hypotheses generated from all three perspectives in a global study of Japanese aid flows. This study seeks to improve the understanding of the Japanese ODA program by addressing some of the gaps in the existing literature. Providing a comprehensive analysis, the article investigates the effects of different political and economic variables on Japanese aid disbursement in eighty-six countries in Africa, Asia, Latin America, and the Middle East from 1979 to 2002. The findings of the study make several contributions to the literature. First, the results provide strong support for the claim that humanitarian concerns, as measured by poverty and human rights conditions in recipient countries, are important determinants of aid allocation. Second, although much of the previous literature has hypothesized that Japan's aid program seeks to promote Japan's economic interests, little empirical support for this view is found in the present study. Likewise, the disbursement pattern of ODA was associated with only a limited number of US security interests; US economic interests are shown to have no effect on ODA.