I am a USC who married a Mexican citizen in December 2007. Do I need to apply for an Individual Taxpayer Identification Number (ITIN) for my spouse if we both live in Mexico City, we have not yet applied for a visa for him, his only income is generated in Mexico, and I plan to file U.S. taxes as "married filing separately" ? I will not claim him as a dependent or an exemption on my tax return, but just by virtue of being married to me, does he need this ITIN?

Last year my husband filed "married filing separately" while we were both living in Canada (he is the USC) and he just made a notation saying "spouse is non-resident alien) and it went through just fine.

Thanks! That's what I was hoping I could do.