The Arizona Petition to Modify Income Withholding Order When All Parties Will Not Sign an Agreement is a legal document used when the parties involved in a child support case cannot agree to alter an existing order. It is filed in the superior court of the county where the obliged (the parent paying child support) resides. The petition must include detailed information about the existing order, the proposed changes, and the reasons the parties cannot agree on a modification. The petitioner must also provide evidence to support their claim that a modification is needed. There are two types of Arizona Petition to Modify Income Withholding Order When All Parties Will Not Sign an Agreement: Petition to Modify Income Withholding Order when Both Parties Agree to Modify (A.R.S. § 25-515) and Petition to Modify Income Withholding Order when All Parties Will Not Sign an Agreement (A.R.S. § 25-517). The main difference between these two types is that in the first one, both parties agree to the changes, while in the second one, all parties must sign an agreement.