The process

The Guatemalan adoption process is, generally, as follows:
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Complete homestudy and dossier
The adoptive family applies for and obtains approval from their local CIS office using the I-600A process; the I-171H is issued by CIS.
The dossier is completed and sent to Guatemala for translation. The dossier is then authenticated by the Foreign Ministry.
At this time, or potentially earlier, a referral of a child is made to the waiting family. The referral is checked to ensure that a properly-issued birth certificate has been issued.
A DNA sample is taken from the child and the biological mother, and sent for testing and verification. The results are then forwarded to the US Embassy in Guatemala City, who will issue a preapproval. This step verifies that the child is indeed the biological child of the birth mother. (4-8 months)
After the family has accepted the referral, a Power of Attorney will be completed. This permits the attorney in Guatemala to act on behalf of the adoptive family.
The attorney presents the dossier and the Adoption Petition to the Family Court in Guatemala. The Family Court will schedule a home visit/ meeting with the biological mother.
Once the Social Worker from the Family Court makes a favorable recommendation, the case and dossier are transferred to the Ministerio Publico (PGN), the entity that approves the adoption and issues a final adoption decree.
Once PGN issues the decree, it is signed by the biological mother, as well as the attorney representing the adoptive family. (4-8 months)
The adoption decree is registered with the Civil Registry, and a new birth certificate is issued under the child’s new name. The child is then taken for issuance of a new passport.
A final package, containing evidence of all of the above steps, is submitted to the US Embassy in Guatemala City. The Embassy will review the package, and if all is in order, it will issue a “pink slip” which indicates an appointment date for issuance of the child’s visa. (about 3 months)
The adoptive family may then travel to Guatemala, and appear at the US Embassy with the child to obtain the immigrant visa for the United States.
The child then enters the United States on the Immigrant Visa. If the child has been issued an IR3 visa, he/she will automatically become a US citizen upon admission. If the child has been issued an IR4 visa, the adoptive family will need to readopt the child according to the laws of the state in which the family lives; upon readoption, the child will automatically gain US citizenship.
total time 8-19 months: could be more or less