An O-1 may be initially issued for a period of three (3) years. Extensions may be obtained in one-year increments only with no defined limit to the period of stay in the U.S. Remember, however, that O-1 is temporary employment to cover an event that is temporary in nature. Therefore, USCIS begins questioning the temporary need of the O-1 employee beyond 6 years. If the employer dismisses the alien prior to the expiration of the authorized stay, the employer is liable for the reasonable cost of return transportation for the alien abroad.