JHMU seeks a high level of interest income exempt from federal income tax. The fund primarily holds investment grade muni bonds of any maturity but may allocate up to 20% of its assets in bonds rated BB or lower. The fund uses a fundamental approach to look for undervalued bonds. The fund manager uses a benchmark index to model portfolio performance and composition, then blends the macro assessment with security analysis. The manager may also incorporate ESG factors in the investment process. JHMU may invest in general obligation bonds, although bonds backed by revenue from a specific public project are favored since these may offer higher yields. To help mitigate the effect of falling interest rates, the fund favors bonds with call protection. And to enhance potential gains and leverage exposure, the fund may utilize tender option bond transactions on up to 15% of its holdings. Note that income paid by the fund may not be entirely tax-free to all investors.