An Arizona Petition to Modify Child Support 15% or More is a legal petition filed by either parent or both parents in the state of Arizona in order to modify an existing child support order by 15% or more. The petition must be filed in the county where the original child support order was filed. This petition can be used to request an increase or decrease in the amount of child support, or to modify other aspects of the existing child support order, such as the duration of the order or the method of payment. There are two types of Arizona Petition to Modify Child Support 15% or More: an “Expedited Modification” and a “Regular Modification.” An Expedited Modification may be granted if the parent requesting the modification can demonstrate a significant change in circumstances that warrants a modification of the existing order. A Regular Modification requires that the parent requesting the modification demonstrate a substantial and continuing change in circumstances, as well as a showing of good faith.