Post-nuptial agreements are similar to marital agreements, except that they are made after a couple`s marriage.  When divorce is imminent, post-uptial agreements are called separation agreements.  becker, l., and kosel, J. e. (1989). “Property Disposition, antenuptial, postnuptial, and property settlement agreements,” in valuation and distribution of marital property, ed. j. p. mccahey. new york: matthew bender. There are several ways to attack a marital agreement in court. These include lack of volunteerism, lack of scruples and lack of disclosure of assets.
 In all U.S. states, it is not permissible to address issues relating to children of marriage, particularly custody and access issues.  The reason is that children`s issues must be decided in the best interests of children.  However, this is controversial: some people think that, as custody disputes are often the worst part of a divorce, couples should be able to settle this in advance.  The laws differ between the two states and the countries, both in terms of the content they may contain and the conditions and circumstances, conditions and circumstances in which a matrimonial agreement may be declared unenforceable, such as. For example, an agreement signed in cases of fraud, coercion or adequate disclosure of assets. Essential terms of the contract. When disclosing the validity of pre-marital agreements, the courts declare that they will not replace their own ideas about what is right with the provisions of the parties` good business. But neither the courts nor the national legislators whose mandates they must respect are not aware of the material fairness of these agreements. It is an amorphous term that the courts determine on a case-by-case basis. Unfair provisions for the parties do not render an agreement materially unjust and therefore invalidating. In the past, couples have entered into pre-marriage agreements with some uncertainty as to their validity.
Today, the presumed validity and applicability of such agreements is no longer at issue in states that have adopted UPAA/UPMAA, including Florida, Virginia, New Jersey and California.  Preliminary contracts in Canada are subject to provincial legislation. Every province and territory in Canada recognizes marital agreements. For example, in Ontario, marital agreements are called marriage contracts and are recognized by Section 52 of the Family Law Act.  Pre-marriage agreements can cover a wide range of topics.