Nuveen AMT-Free Municipal Credit Income Fund's investment objectives are to provide current income exempt from regular federal income tax and to enhance portfolio value relative to the municipal bond market by investing in tax-exempt municipal bonds that the Fund's investment adviser believes are underrated or undervalued or that represent municipal market sectors that are undervalued. The Fund invests in municipal securities that are exempt from federal income taxes. The Fund uses leverage. By investment policy, the Fund may invest up to 55% of its managed assets in municipal securities rated at the time of investment Baa/BBB and below or judged by the manager to be of comparable quality.