Hello friends, I am a graduate student with Master degree and I graduated in May 2012. Now I am in OPT period. I got a job in a small office but got laid off after two months. After that the same office asked me to do some works for them when they needed. So, I worked for them like 2-3 times from home and sent them the works through the email. Now the problem is the payment issue. They are trying to pay me for the works that I had done and therefore asking me to fill up W-9 form for tax record. When I went through the instructions of W-9 form, I felt like I can't fill the form because it says that it is for US person only.  So, I am wondering if I can fill the W-9 form or not?? If I do now, will it affect me in future? (for green card issuance and all...). I am really worried about it. Hope to get your useful directions soon...... Thanks for your time and consideration.  :)