If you are in the U.S. and you are applying for a family-based green card, have a K-1 fiancé visa, or are the spouse of a H-1B visa holder, then you may be able to apply for a work permit (Form I-766) so you can work while you are in the U.S.. Students who are studying in the U.S. with a F-1 student visa may also wish to apply for a work permit.