The term dissolution of marriage refers to the ending of a marriage through legal proceedings, the same as divorce. In many jurisdictions, a couple may file a petition for the court to terminate their marriage pursuant to a written agreement between the parties. Such an agreement must cover all issues pertaining to the dissolution, allowing the matter to be concluded without a hearing or trial.
In most jurisdictions, divorce and dissolution of marriage are the same thing, each requiring the same legal proceedings to finalize. The proceedings may be adversarial, or the parties may work together to come to an agreement regarding all issues of distribution of marital assets, and payment of spousal support, as well as child custody and child support, if applicable.
If an agreement is reached, it is documented in a Marital Settlement Agreement, and presented to the court for approval and a final divorce order or decree. Any issues not settled between the parties may continue to trial, during which both parties will present argument, testimony, and other evidence to make their case. Leaving these things for the court to decide is a more expensive avenue for most litigants.