RESIDENCY REQUIREMENTS:  Mexican adoption procedures include a one to three week pre-adoption trial period during which the child lives with the prospective adoptive parents in Mexico .  The adoption is not final until this time, and the child cannot leave Mexico before it is complete.  Because of the large amount of paperwork in both the Mexican and U.S. processes, DIF suggests that the adoptive parents be prepared to spend at least three months in Mexico including the pre-adoption trial period.