hey euta nepali, that's the exact process to obtain an ITIN.......u have to fill the form W7.......u have to prepare ur tax return and have to write applied in the space which asks for ur wife's SSN......the tax return along with the form W7 and a notarized copy of her passport should be send to the IRS (it should be sent to philadelphia, i think, check in the IRS website by searching for form W7)......the IRS will assign an ITIN to ur wife and will process ur return..... hope this helps......