In the American legal system, a petition for dissolution of marriage is a document that is filed to begin legal divorce proceedings. The information required on the document may vary from region to region, but most petitions establish the general circumstances of the divorce proceedings and allow the court to know which considerations, such as assets, spousal support agreements, and custody of children, will be a part of the divorce process. Filing a petition for dissolution of marriage is generally the first legal step taken in divorce proceedings, but can usually be withdrawn if the couple reconciles or decides to postpone divorce.

A petition for dissolution of marriage is typically filed in a county in which the filer has established residency. The amount of time required to establish residency varies from region to region; for example, in California, a petitioner must be a resident of a county for at least six months before being able to file for divorce in that county. The county where the petition is filed will be the site where all legal proceedings, such as divorce or custody hearings, will take place.

Information for a petition of dissolution of marriage will include the names and known addresses of both married partners, as well as the names, addresses, and ages of any children that have resulted from the marriage. Typically, the form will also ask for a reason for the divorce, although many areas have “no fault” laws, which only require that irreconcilable differences be cited. A petition for dissolution of marriage usually also requires a list of all assets, property, income information, and debts of both parties involved in the divorce.

Depending on the regional laws, some courts will allow financial agreements, including terms of spousal support and division of property, to be settled by the couple outside of court. In these cases, a summary of the agreements is often requested, and both parties usually sign the document indicating the terms are acceptable. In some cases, if a division of assets seems unfair to a judge, he or she may step in to discuss or order alterations to the agreement.

Many regional courts offer separate versions of the petition for dissolution of marriage depending on whether the couple has children. Couples with children will usually fill out a lengthier form that includes requests or information regarding custody of minor children. These forms are used as a jumping-off point for custody decisions, particularly if there is a dispute regarding custody between the parents.

Although a petition for dissolution of marriage can be filled out independently, some legal experts recommend seeking legal advice or help filling out forms correctly. Especially in the case of a contested divorce, the information on these forms can factor into a judge's decisions regarding custody and division of assets. Additionally, because divorce is often a stressful and emotionally trying situation, consulting a lawyer or low-cost legal aid firm can help a petitioner focus on the requirements of the form instead of the emotions of the situation.