These kinds of agreements are very common for persons starting new families, with existing obligations to ex-spouses and children from a prior marriage.

Premarital agreements are also useful for first time spouses in which one (or both) of the parties bring substantial assets or liabilities to the marriage. With exceptions, this is straight contract law and gives the parties wide latitude to be creative with regard to how they want to define their legal relationship with respect to property holdings, earnings, and spousal support.