A husband (defendant) and wife (plaintiff), both residents of Massachusetts, married and continued to reside in Massachusetts for ten years, during which time they had two children. They later moved to New Mexico, then Oregon, where they divorced in the summer of 1997. That same summer, the wife and children returned to Massachusetts and the husband moved to Idaho. Pursuant to the Oregon divorce decree, the husband was obligated to pay $750 per month in child support until the children reached 18 or, if a child was attending school, 21. The decree did not specify how college expenses would be handled, but the parties intended to contribute jointly to those costs. In time, the wife brought suit against the husband in Massachusetts, seeking an order that he contribute to college expenses. The Massachusetts court ordered the husband to reimburse the wife for half of the college expenses she had paid thus far and to contribute 40 percent of future expenses. He appealed on the ground that the court lacked subject-matter jurisdiction under the Uniform Interstate Family Support Act (UIFSA), which was adopted as Massachusetts law.