Nuveen Municipal Credit Opportunities Fund (NMCO) seeks to provide a high level of current income exempt from regular U.S. federal income tax and secondarily, total return. The Fund invests primarily in high yielding, low- to medium-quality municipal securities that, at the time of investment, are rated Baa/BBB or lower or, if unrated, are judged by the portfolio managers to be of comparable quality. No more than 30% of the Fund's managed assets will be in municipal securities rated CCC+/Caa1 or lower at the time of investment or unrated but judged to be of comparable quality. No more than 10% of the Fund's managed assets can be in defaulted securities or securities of issuers in bankruptcy or insolvency proceedings at the time of investment.