A type of trust that allows taxpayers who are not U.S. citizens to claim the marital deduction for estate-tax purposes. Spouses without citizenship are not eligible for the marital deduction without a qualifying domestic trust. QDOTs are similar to QTIP trusts in that the marital deduction is conditional upon the inclusion of assets inside the trust. Although establishing a QDOT is often easier and faster than applying for citizenship, this type of trust is not without risk. There are numerous provisions pertaining to this type of trust that must be obeyed carefully in order for the trust to remain valid. QDOTs apply only to spouses of decedents who died after November 10, 1988. At least one trustee must be either a U.S. citizen or domestic corporation that is authorized to retain estate tax out of the trust assets.