This webpage contains advice for people asking for a letter of recommendation from me or someone like me. It was largely plagiarized from a similar page by Ravi Vakil. (Last modified Friday, 30-Mar-2018 12:11:46 EDT.)

Special warning (may not apply to others like me): given that I have limited time to write these letters, I would prefer to prioritize supporting the careers of deserving younger mathematicians. As a consequence, I am no longer accepting requests for recommendation letters for promotions beyond the tenured Associate Professor level (or equivalent). In the typical case where such a request is issued by an evaluation committee rather than a candidate, it will be met with a polite one-paragraph reply summarizing my opinion.

You likely have a lot of things on your mind right now, and this is the last thing you want to worry about, but this deals with a central part of your application.

Letter-writing is one of my most important duties. Precisely because it is so important, I am asked to do it many times each year at numerous levels (undergraduates applying for graduate school or summer employment, graduate students applying for postdocs, postdocs applying for tenure-track jobs, tenure cases). This makes the following request all the more important: Please remember that it is in your interest to make your busy letter writer's job as easy as possible.

Please give me as much notice as possible so I can write as detailed a letter as I would like. A month is reasonable. Two weeks may be pushing it if there isn't much flexibility in my schedule at that time. If you give me very little notice, your letter will necessarily be rushed, which is in no one's interest.

You want to help your recommender write as detailed a letter as possible. Here are things that would help me. Only some may apply to you (especially if I have written for you before). I will likely only start writing your letter once I have all the information I would like (as there is always someone else's letter I can write first). If some of these materials are online, a URL will suffice for those. I strongly prefer electronic versions to paper.

Thank you for helping make this process run smoothly, and good luck with your applications!