Charitable organizations form a vital part of America’s safety net. Ideally, foundations would be able to make greater payouts in hard economic times when needs are greatest. Unfortunately, the design of today’s excise tax on foundations undermines and in fact discourages such efficiency. Under current law, private foundations are required to pay an excise tax on their net investment income. The tax rate is 2 percent, but it can be reduced to 1 percent if the foundation satisfies a minimum distribution requirement. The dual-rate structure and distribution requirements obviously introduce complexity. The stated purpose of the tax in legislative history—to finance IRS activities in monitoring the charitable sector—has never been fulfilled. In the recent recession, the impact of the excise tax was especially pernicious, as it penalized those that maintained their level of grantmaking. How?  As Martin Sullivan and I first described in 1995, the excise tax penalizes spikes in giving; under the current formula, a temporarily higher payout results in a higher excise tax when payouts fall back to previous levels. A foundation that reduced its grantmaking during the last recession would not be subject to an increased excise tax because the amount the foundation paid out would be measured as a share of current net worth. One proposal would replace the excise tax with a single-rate tax yielding the same amount of revenue. While a flat-rate tax would remove the disincentive to raise grantmaking in bad times, it still raises taxes for some foundations and not others. A related law applying to foundations is the required payout rate, now set at 5 percentage points. Many experts have debated how high that rate should be. The current rate is believed to approximate the long-term real rate of return on a foundation’s balanced portfolio of assets. However, if foundations follow a strict rule of paying out the minimum 5 percent every year, they, too, will be operating procyclically, paying out more in good times when stock markets are high and less in bad times. If we wish foundations to operate more countercyclically—to pay out more when needs are greater—we need to address both the excise tax and the natural tendency, reinforced by a minimum payout requirement, to make grants and payouts as a fixed percentage of each year’s net worth.