The marital deduction allows one spouse to pass an unlimited amount of property to the other spouse by will or by gift without incurring any Federal estate or gift taxes. However, this advantage is not necessarily available to non-citizen spouses without careful estate planning. Through the use of a qualified domestic trust (QDOT) property can be left for the benefit of a non-citizen spouse without incurring federal estate tax. While the rules governing qualified domestic trusts are complex, if the rules are followed precisely, federal estate tax will be avoided in a similar manner to the unlimited marital deduction enjoyed by citizen spouses.