Before you have even chosen an agency, there are steps you can be taking on your own. And since the wait for some of this paperwork to be processed can often be months, it's a good idea to get started as soon as you are sure you want to adopt from Cambodia.
First, you need to apply to the INS. The form you need can be downloaded off the web: USCIS Form I-600A After you fill out and mail in that form (with a check or money order), the INS will make an appointment for you to go in and be fingerprinted. (Often the "appointments" cover a month or so, and you go in when it is convenient).
Also, you need to get a passport, or if you already have a one, it should not expire in the next 14 months. The U.S. State Department has a passport services web page. At that site you can download the passport application form, find locations for applying for your passport, as well as find answers to your questions about getting a passport. This is another step to do right away, because process times can be long. (For an extra fee your application can be expedited, but it can be pricey.)
Another good step to take right away is to request copies of your birth, marriage and divorce certificates. These only need to be certified copies, Cambodia does not require them to be authenticated. The Assistant Stork has a great database of every state's departments of vital records and Secretaries of State. Be sure to ask for at least 2 copies of each document.
This is only the beginning of the paperwork you will need to do before your dossier will be ready to send to Cambodia. It's also a good idea to find a friendly notary, because you will be needing them to notarize nearly 100 pieces of paper when all is said and done.
Your next step is to pick an agency... (although in Cambodia, you can also adopt independently, or semi-independently).
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