For better or for worse, all marriages end. The rights and obligations attendant to the termination of a marriage vary, even within the same jurisdiction, depending on whether the marriage ends by reason of divorce or death. Planning for the termination of a marriage, by either cause, requires the knowledge of both matrimonial and trusts and estates laws, and how they intersect. Within the United States, we are already familiar with dealing with conflict-of-law issues when the laws of more than one state can apply. In the case of multistate and international couples-couples of different states or nationalities, or who have residences, other property or children in more than one jurisdiction-such planning additionally requires the knowledge of how matrimonial and trusts and estates laws intersect in more than one state or country.

The termination of a marriage by divorce is almost always contested. Increasingly, the termination of a marriage by death is becoming contested as well. The ability to use agreements either before, during or after marriage to plan for the termination of one's marriage varies widely from jurisdiction to jurisdiction. For multistate and international couples, the process is all the more complicated, as one must consider the different treatment in each applicable jurisdiction of such complex issues as:

Taxation of property settlements, alimony and child support: The rules vary widely from country to country whether the making of any of these payments is deductible, whether the receipt of these payments is taxable, and whether the tax attributes of any such payments may be agreed upon by the parties, or altered by recategorizing one type of payment as another. The ability to secure a foreign tax credit or similar relief in one country for such taxes in the other country also varies.
Estate planning opportunities incident to divorce: The rules for whether, and if so the circumstances under which, transfers incident to divorce are supported by consideration or are otherwise exempt from transfer taxes also vary widely from country to country.
Forum shopping: The grounds for divorce, the guidelines for determining custody, property settlements, alimony and child support, the relevance of fault, and the susceptibility of the courts to external influence similarly vary widely from jurisdiction to jurisdiction.
Immigration marriage fraud: Many countries will not enforce agreements with respect to so-called "marriages of convenience."
International parental kidnapping: Nearly all countries have become increasingly sensitive to policing parental kidnapping that potentially removes a child from its jurisdiction.
Subject matter jurisdiction: Not all states and countries have the same, or even compatible, bases for establishing the requisite contacts necessary to support subject matter jurisdiction over a couple's marriage, including whether the mere contractual selection of a jurisdiction by the couple will suffice.
Efficacy of discovery procedures: The existence and adequacy of discovery procedures varies widely from jurisdiction to jurisdiction, particularly with respect to the discovery assets of offshore trusts.
Security for post-marital obligations: The necessity of and requirements for posting security for post-marital obligations similarly can be dramatically different from jurisdiction to jurisdiction.
Enforceability of foreign judgments: A matrimonial judgment from one country may or may not be enforceable, in whole or in part in another country; in the worst case, the question might have to be determined "ab initio."
Upholding secular aspects of religious law: Different countries have different rules on whether the secular aspects of religious divorce and religious marital contracts can be enforced in secular courts.

Pre- And Postnuptial Agreements
The U.K., France and the U.S. represent three different but typical legal and societal approaches to the ability of parties contractually to regulate, broadly speaking, their marriages: seldom, most of the time and some of the time, respectively.

In the U.K., pre- and postnuptial agreements have historically been unenforceable. While they continue to remain unenforceable, the courts in appropriate circumstances are beginning to look at pre- and postnuptial agreements as a guide on how to exercise their inherent discretion-including whether or not to assume jurisdiction over an international marriage in the first instance. Ironically (given that the genesis of the trust can be traced to England), trusts are largely disregarded by the courts in resolving issues of support, maintenance and property settlements, and trusts created within three years of marriage may be assumed to be fraudulent in this regard.

In France, couples have the opportunity to select the type of separate or community property regime that will regulate their marriage. Separate property is the best for divorce, but may leave no flexibility in terms of tax planning at death. Community property, which is the default regime, will result in an even division of property upon both divorce and death. Electing universal community property affords complete tax protection upon the death of the first spouse to die, but requires that all of one's property go to one's spouse upon divorce. Parties may change regimes during marriage, but only with court approval. Divorce itself must be decided by the courts.

In the U.S., pre- and postnuptial agreements are commonly used and generally enforceable. There is no requirement that the spouses be separately represented, although separate representation will bolster an agreement against subsequent challenge. The extent to which asset disclosure is required for a prenuptial agreement varies widely from state to state, although virtually all states require asset disclosure for postnuptial agreements. Agreements generally need not be witnessed and need only be signed and in writing-although agreements between nonmarried couples may be oral and even implied. Opposite sex couples may be eligible for common law marriage in certain states. Agreements may provide for property settlement, may provide reasonable limitations upon spousal support, and may provide or waive testamentary obligations; they may not, however, fix child support.

There has been a noteworthy increase in the use of postnuptial agreements in recent years. This reflects situations where there has been a rapid, perhaps unanticipated, increase during marriage in either (i) the creation of wealth (say, one member of the marriage is a hedge fund manager or Internet product/new media creator) or (ii) the transmission of wealth (say, estate planning being done by newly wealthy parents of one member of the marriage). Many times, people will not engage in a proposed high-risk business venture or gratuitous transmission of wealth unless they know that the assets involved are protected. It is generally in the interests of both members of the marriage to afford the assurances being sought, particularly where the alternative is that the venture or transmission will not be entered into at all. In such instances, post nuptial agreements are truly part and parcel of an integrated, intergenerational estate plan and can frequently avoid the use of more restrictive trusts and other entities.

Inheritance Disputes
In the U.K., family dependency and inheritance laws permit the rewriting of a will that fails to provide for the reasonable support of a testator's spouse and minor children. Indeed in the case of a surviving spouse, the test is gravitating from that of "needs" to one of "fairness."

In France, holographic wills are valid but readily subject to contest, whereas wills executed before a notaire are much harder to contest. A spouse's entitlement is typically dictated by the marital regime, and one cannot disinherit one's children with respect to one's disposable property.

In the U.S., only Louisiana has forced heirship. A spouse's testamentary share is usually a fixed percentage, without reference to actual support needs. Both the percentage and the asset base against which the spousal share applies varies from state to state and can be an intestate share in the absence of a will or an elective share against a will (which may or may not be avoidable through use of testamentary substitutes and may or may not be able to be satisfied with a trust), as contrasted with community property or equitable distribution upon divorce. A will can typically be contested only on the grounds of (i) improper execution; (ii) lack of testamentary capacity and (iii) fraud, mistake or duress (e.g., undue influence). Agreements, however (such as prenuptial agreements, separation agreements, and even shareholder and partnership agreements) supercede wills. In terrorem clauses are effective in many states, but never to defeat an elective share.

As the forgoing demonstrates, whether or not, and how, to plan for the termination of a marriage, and whether by death or divorce, requires an economic and legal analysis of the comparative rights and obligations attendant to the aspects of marriage potentially regulated by each applicable jurisdiction.