A "power of appointment" gives the beneficiary of a trust the power to decide to whom the trust's assets will be distributed, either while the trust is still in existence (an inter vivos power of appointment) or when the trust terminates on the beneficiary's death (a testamentary power of appointment). A "testamentary" power of appointment usually must be exercised in the beneficiary's Will and, as noted, the power only becomes effective on the beneficiary's death. Powers of appointment may be "limited" so that the group of people to whom the trust assets may be given is restricted, or "general" so that the beneficiary may give the trust assets to his/her estate, and thereby, to anyone named in his/her Will. Possessing and/or exercising a limited power of appointment has no tax consequences for the beneficiary, while merely possessing a general power of appointment makes the trust assets includable in the beneficiary's estate at death (sometimes that is done on purpose, to avoid the more onerous GST tax, for example). One benefit of giving the primary trust beneficiary a testamentary power of appointment over his/her trust is that the beneficiary can address changes that have occurred over time. Since many trusts last for a very long period of time, changes may need to be made to the distribution of the trust assets on the beneficiary's death. For example, suppose a trust beneficiary has two children. Sometime after the beneficiary's trust was established, one of the beneficiary's children invents a popular product and sells it to a large corporation and becomes very wealthy, while the beneficiary's other child develops a debilitating disease that prevents that child from working and results in large health care expenses each year. The "default" in the instrument that created the trust is likely to provide that the assets in the beneficiary's trust are to be distributed in equal shares to his/her two children upon his/her death. By exercising the testamentary power of appointment, the beneficiary can change that default distribution and provide a larger share (and a special needs trust, if applicable) for his/her child who is seriously ill.