Naturalization is the legal process through which a foreign citizen or national can become a U.S. citizen. In order to be naturalized, an applicant must first be qualified to apply for citizenship. Then, he or she must complete an application, attend an interview, and pass an English and a civics test. Upon successful completion of these steps, the applicant takes an oath of loyalty, and becomes a citizen. These legal requirements help the immigration service ensure that only those people who are sincere in their desire to become Americans become naturalized.