In order to naturalize as a citizen of the United States, the initial requirement for all applicants is to be a Permanent Resident (i.e. have a Green Card). Depending on your situation, you’ll need to have been a permanent resident for at least three to five years prior to applying for citizenship. In addition, you must be at least 18 years old when you file your naturalization application; be able to speak, read and write basic English; and be a person of good moral character. For many of the requirements, certain exceptions apply and it’s useful to consult with an attorney to see whether you qualify for requirement exemptions.