From time to time you will need a letter written about your status as a student here. Some of the reasons are: You will be travelling, you need to apply for OPT, you need verification of your status for an employer, etc. If you need such a letter, here's what to do:

Email cthornton@jhu.edu or visit Cathy Thornton in NEB 224 and tell her the reason for the letter, to whom you want it directed (can be "To Whom It May Concern"), when you plan to complete your course of study and who is advising you. If there is any specific wording you want included, please mention it. Let me know when you need the letter, and I'll print it out on department letterhead.