The effects of foreign expansion on the market values of U.S. banks (USBs) are examined in this study. The results show that shareholders of USBs experience significant abnormal returns of -0.17 percent when banks announce foreign expansions. Abnormal returns are insignificant when the announced mode of expansion is through a representative office, are significantly positive for announcements related to branches, and are significantly negative when the announced mode of expansion is through formation of a joint venture or a subsidiary, or through an acquisition. Abnormal returns are significantly negative when banks announce expansion into developed countries, and are significantly positive when announcements relate to risky developing countries. Post-announcement changes in the total variance of returns and in the unsystematic risk of USBs are inversely related with abnormal returns. Higher wealth effects are associated with higher levels of prior overseas experience.