Family-based immigration allows U.S. citizens and lawful permanent residents to sponsor their relatives for immigration to the United States. This process helps families reunite by granting visas to spouses, children, parents, and siblings, depending on the sponsor's immigration status. The U.S. Citizenship and Immigration Services (USCIS) oversees family-based immigration applications. There are two main categories: immediate relatives, who have a more straightforward path, and family preference categories, which may have longer wait times due to annual visa limits. This system emphasizes the importance of family unity in immigration policy.