I was on an H1-B visa, and on an F1 student visa before that. I hope to throw some light on the nuances of resigning from your position in a US-based organization and staying on the right side of the Man !

The duration of your stay is determined by the date stamped on the Form I - 94 . Some other forums I looked up say that technically, your stay is legit only until you are a paid employee of your employer. So if you quit your job, going by some rules you're out of status and must leave the U S immediately. However, this is a rather unreasonable proposition if you've stayed in the US for any reasonable length of time. At the very least, you'd be hard pressed to find a decently priced plane ticket home within 48 hrs !

We've now entered a rather gray region in the rulebook. The right way to go about this is to file a Form I 539 asking for an extension of stay and cite your reasons. Of course, an even better option is to speak to an immigration lawyer before you put in your papers with your employer.

(It is my understanding that once an I 539 is filed, you must leave the country in the time specified in the form. So if you get another job in the US after filing the I 539, you will be required to leave the US, get a fresh H1B stamped and then comeback. Like I said, an immigration lawyer is a good idea before you put in your papers !!)