Qualified Terminable Interest Trust

When one spoue dies, the other spouse can take any property and have it exempt from estate taxes. If you want the deduction but don't want the surviving spouse to have the ability to control who gets the property next. Only trust that gets this result.

Normally, an estate for estate tax calculations includes all of the deceased's property. If the person that dies was married, they can transfer their property to their living spouse. The transferred property is not going to be included in the estate but has to be included in the survivor's estate when they die. It's a way to delay but not avoid estate taxes.

But if property goes to the surviving spouse, what are they going to do with it. Maybe they will remarry and give it to their new spouse, or worse it could end up with the children of the new spouse. 

So a way to keep some control of what happens to the property while avoiding the estate tax problem, is to create a trust that gives the living spouse income for life but then it goes to someone else when they die. And this can't be changed by the living spouse. 

If you think about property in a trust, it can do different things. I can apprecate in value but give off no income, or generate income but not go up in value. Since one person wants income and the others want greater value, it can cause problems.