A United States Permanent Resident Card is an identification card confirming the permanent resident status of an alien in the United States. The Permanent Residency Visa or "Green Card" serves as proof that its holder has official immigration status and makes is a permanent resident of the United States. Permanent residency allows you to live and work in the United States for the rest of your life. Generally, a permanent residency visa can be applied for in one of two ways. You can either apply for a Green Card through a family member or through an employer. You must go through a multi-step process to obtain permanent residency. This process varies depending on your particular circumstances. In most cases, applicants are required to fill out a permanent residency application form, complete an immigrant petition, and undergo a medical examination as part of the process. You will need to include a photograph of yourself, and attend an interview as well. The permanent residency Green Card application process can take several years to complete, depending on the applicant's country of origin and reason for applying. Most immigrants will be granted a temporary Green Card first, and then must apply for a change of status for a permanent green card within a specific time period (usually two years). Before a Green Card holder can apply for permanent citizenship via the naturalization process, he or she needs to fulfill a residency requirement.