Recommendation Letters

Please read this entire page.

I will usually consider requests for recommendation letters from students who meet any of the following criteria:

  • You were a TA on my course staff.
  • You are an official advisee of mine.
  • You have worked one-on-one with me in some capacity.

I usually need 4 weeks lead time. I don’t suggest asking for a letter with less lead time than that, unless we know each other well and I’ve already written you a letter before that I can adapt.

If you have only taken a 3000 or lower level class with me, I’m unlikely to agree to write you a letter. We would have to have gotten to know each other well, which doesn’t typically happen in those (large) classes.

You will usually be given an option to waive your right to view the letter I write. Most students do. If you’re not going to waive that right, then you and I should have a conversation about why you think I’m the right letter writer for you.


I will need the following information to write a letter:

  • A link to the program to which you are applying.
  • A summary of all the ways in which you and I have previously interacted. Assume that I’m terribly forgetful.
  • A list of all the courses you’ve taken with me, including the semesters in which you took them, and the grade you received (which I will double check).
  • A current resumé or CV.
  • A copy of your personal statement or statement of purpose, if the program to which you are applying requires such a statement.

PhD Letters

If you are applying to a PhD program, we need to meet at least once before I will agree to write a letter. I need to understand why you believe (i) that a PhD is necessary for your future goals, and (ii) that I’m a good choice to be a letter writer for you.

Applications to CS PhD programs are often due in December around the time of finals. Recommendation letters are typically portrayed to you by universities as being due at the same time. In reality, those letters won’t be read at least until other faculty have time to read them—that is, after their own finals are over. So, it won’t be a problem if my letter for you is not submitted until near the end of December.

Internal MEng Letters

If you are a Cornell undergraduate applying internally to the Cornell CS MEng program, I will probably wait to write the letter until the Admissions Committee asks for one. So, don’t worry if it’s after the deadline and I still haven’t filed a letter. Sometimes I just talk with someone on the committee directly (or send an email) instead of going to the trouble of a formal letter.