In general United States Citizenship is acquired by birth, registration, transmission, or application. All persons who are born in the United States are, by law, United States citizens unless their parents are diplomats. Persons born outside the United States to United States citizen parents are entitled to citizenship, however the birth must be registered with a United States embassy or consulate. If you are born outside of the United States and one of your parents is a United States Citizen, it is possible that citizenship can be transmitted to you through your parent. There are several determining factors involved and an attorney should be consulted to discuss the matter. The last option to acquire United States citizenship is to apply for it. Permanent residents who obtained permanent resident status based upon their marriage to a United States Citizen are eligible to apply for citizenship three years after they obtain status as a permanent resident. If status as a permanent resident is obtained otherwise then the waiting period to apply for citizenship is five years.