you may have to fill out Form 90-22.1 every year if you own or have an investent in any foreign bank accounts or other types of financial accounts based outside the US
This is separate report from your tax return, but you can file them together.
You MUST record accounts you hold in foreign banks and other financial institutions if your total balance across all your accounts is $10,000 or greater at any time during the year.

I'd like to add an important point to Daiva's response. Don't forget to examine whether Form 8938 (Specified Foreign Financial Assets reporting) is also required to be filed with the Form 1040. This is a relatively new requirement brought into effect with the enactment of FATCA in 2010. You can read more about Form 8938 on my tax blog posting here: http://blogs.angloinfo.com/us-tax/2012/03/19/new-filing-requirements-for-2011-tax-returns/