Would you like your assets to last forever? Of course, there are no guarantees, but a "dynasty trust" could help you preserve wealth for your heirs indefinitely. As the name implies, this type of trust is designed to span several generations, barring drastic changes in applicable laws or your family's financial circumstances.

Under a common law principle known as the "rule against perpetuities," trusts normally are required to have a beginning, middle, and an end. This rule was adopted in many states, establishing an expiration date for trusts of 21 years after the death of a potential beneficiary who was alive at the time of the trust's creation. California and other states have adopted a variation of that rule with a limit of about 90 years. Delaware is among the few states that have repealed the rule completely and actively encourage people to set up dynasty trusts in those states.

With a dynasty trust, you transfer selected assets—perhaps stocks, bonds, real estate, or a combination of those—to a trust managed by an independent trustee. The trust can be created as an "inter vivos" transfer during your lifetime or a testamentary transfer through your will. Once established, the trust is irrevocable—you give up control over the assets and the right to change beneficiaries.