Current regulations do not allow you to be the US citizen sponsor of a "boyfriend" (other than to provide him with an "invitation letter" for him to present to US Consular authorities in the Dominican Republic for the possible issuance of a B-2 tourist visa, assuming he can convince the consular authorities of his non-immigrant intent and be able to properly document strong ties, economic and otherwise, to the Dominican Republic). However, if he is your "fianc?" and you contemplate marrying him within 90 days of his admission to the US, you may begin a petition process with USCIS relating to a K-1 Fianc? visa. The K-1 process usually takes between 5 months to over a year (depending upon the government's current processing backlogs) for a decision to be made by USCIS and then requires that he consular process in his home country to actually receive the K-1 visa for travel to the US. You should consult and work closely with experienced immigration counsel to guide you through the process.
Answered on Aug 08th, 2012 at 11:50 AM