If the divorce process is like climbing a mountain, getting a divorce in another country is like scaling Mount Everest. When one of the partners has dual citizenship and is living outside the United States, the cost and time increase exponentially. The American Academy of Matrimonial Lawyers doesn't have an exact count of two-country divorces but the evidence suggests the number is growing. Overseas courts are often a complete mystery especially when trying to resolve child custody, asset division, and visitation issues.
Keep in mind that it does not matter where a couple was married, what matters is where they decide to divorce. Where you live determines where the case will be heard, even if one of the partners is not a citizen of that particular country. For example, a wife holding dual U.S. and British citizenship living with her U.S. citizen husband in London would have to dissolve the marriage in English courts. Sometimes it's a race to the courthouse because the party that files first sets the venue.
Something else to consider: When it comes to property division, the court handling the case has the final say, even if the property is in another country. But winning the court case and actually taking possession is another matter, and can land the winner in another battle in an unfriendly foreign court. Same thing with collecting child support from an overseas ex-partner. The custodial parent may have to travel to get the money.
In cases where one partner alleges the other kidnapped the children and took them overseas, be prepared for additional heartbreak. The U.S. State Department can facilitate conversations with authorities in the other country, but if that government awards custody to the alleged kidnapper there is almost nothing that can be done. The laws of the country where the children are rule. One man who lost his children to overseas parental kidnapping advises, "never get your kids passports."
Source: Reuters, "Divorce in two countries is double the trouble," Geoff Williams, Oct. 24, 2012