Often foreign nationals are admitted in one category and apply for a change of status (COS) to another category while in the U.S.  Recently, USCIS issued a memorandum reminding applicants applying for COS that if they traveled abroad while the application was pending, their application would be considered abandoned and USCIS would issue a denial. Traveling abroad will also result in a denial of any Form I-765, Application for Employment Authorization, filed before the COS is approved.   Therefore, if you are planning to travel abroad you must strategize the filling of any application for COS.