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The Scarlet Letter: Tips for Obtaining the Best, and Avoiding the Worst, in Your Letters of Reference

Imagine this nightmare scenario: you have worked hard for years on a difficult project with a difficult advisor. The end, at last, is in sight. You're ready to defend your thesis (if you're still a student) and apply for jobs. But after several months and dozens of applications, you are still receiving rejection-only letters. You can't figure it out.

Another member of your thesis committee or a friendly faculty member in another department finally bugs one of her colleagues until he gives you an interview. During the interview, your prospective postdoctoral employer explains his dilemma: Your record is good, and you are a promising candidate ... but the letter of reference from your advisor is NOT.

This story is the reality for more people than you'd imagine. In some cases, the advisor and the student have had a truly terrible relationship (see my column on the Story of L. for an example), but in other cases the advisor has simply failed to provide the kind of endorsement that is suitable--or sufficient--for the job.

The result is the same: The researcher's job prospects are dimmed considerably.

Most of you probably think that the letter your advisor writes is completely out of your control. After all, it is your advisor's opinion--not yours--and the letter is confidential. Surprise! You can actually exert a significant influence over the content and tone of letters that are sent out on your behalf. With careful planning and good communication, you may even mitigate the negative things that a reference may put in the letter.

What is a good letter of recommendation?

Having reviewed applications for a number of fellowships and several postdoc positions, I have had the opportunity to see the full range--from stellar to abysmal--of letters of reference. You might think that the difference lies only in the range of praise given. However, even stellar achievements may not get the treatment they deserve if the structure and tone of the letter is lacking.

The best letters of reference tend to have the following characteristics:

  • The writer is known and respected by the reader. (He or she is either a colleague or is well-respected throughout the community.)

  • The writer gives specific and meaningful examples of achievements and provides specific stories that illustrate the candidate's strengths.

  • The writer provides quantified assessments of the candidate's abilities, especially with respect to other scientists.

  • The letter addresses the most important skills and traits needed for success in the job.

  • The letter is long.

For example, a strong letter might say things like:

"Richard is an outstanding researcher, in the top 3 to 5% of the graduates from our institution over the last 10 years. He has the drive, creativity, and ability to become a leading research astronomer, even in this tough job market."

In contrast, a weaker letter might read:

"Richard has shown dedication and drive throughout his years as a graduate student. He has the capacity for continued productivity in the field of astronomy."

It's fairly obvious which is the stronger endorsement.

Think Like Your Advisor

Consider the letter-writing process from your advisor's perspective. He or she is most likely to genuinely care about your success and will be willing to write as positive a letter as possible. However, they are also busy. Writing your letter of reference may represent just one action item on their weekly to-do list.

They may also not have much direct information about the opportunity (or opportunities) you are seeking. And while they will usually have a good idea how to write a recommendation letter for a postdoc or faculty position, they may be clueless about what to say if you are applying for a Congressional Science Fellowship or a nonacademic internship. All this can result in a lackluster letter of reference.

The Keys to Superior Letters of Reference

There are some obvious ways to help your reference create a better letter:

  • Give your references plenty of time to accomplish their tasks. Telling them that you need a letter by the next business day will not only throw their world into turmoil, but it will also speak volumes about your inability to plan and organize! Give them plenty of advance warning.

  • Remind them of the deadlines and check back periodically. Even the most well-intentioned reference may slip up, get confused about deadlines, or lose some information. Periodic reminders will NOT be resented--your references may actually be grateful.

  • Thoroughly prep them. A good strategy is to give your references a memo which describes the job or jobs to which you are applying. Include a copy of the job description and any other material. In your memo, specifically tell them which key skills or attributes are important and the specific things in your background they may want to mention. This will help you come as close as you are comfortable to drafting the letter for them.

Know Their Mind BEFORE Asking for a Letter!

It would be ideal if you could know how good a recommendation letter your reference was going to write BEFORE you ask them. While you can't read minds, you probably can make a solid assessment about the health of your professional relationship. This will be the best indicator of the quality of endorsement. There are some useful strategies for assessing this.

One strategy is the direct approach: Sit down with the prospective letter writer and discuss your career plans. Directly ask the person if your career goals are realistic or if you need to become more competitive. This may be a very difficult discussion to have, but believe me, it is much better to get these issues aired at the start.

At the worst, you both may realize that there is a disconnection between your career goals and your advisor's preferences, or between respective perceptions of your work-related performance. At the best, you may discover that your advisor is much more supportive of you than you realize and may have some great advice for you.

The other strategy is the indirect approach: Talk to the most trusted mentor you have (possibly a member of your research committee or even a collaborator from another institution) and ask him or her to "sound out" your advisor. Your mentor will probably get candid comments that he or she can use to build an assessment of your advisor's mindset. While it is unlikely that your mentor will share the gory details of their conversation, he or she should be able to indicate how willing your advisor is to be your advocate.

What if your advisor will NOT write a strong letter?

Many students and postdocs worry that their advisor's disapproval will sink their career on the spot. This issue can be mitigated with some careful strategy. First, it is important to understand the nature of your advisor's criticisms. You may get this either from a direct conversation or through indirect methods (depending on the policies in your department, you may be able to see your personnel file with your yearly evaluations). Second, once you have a good handle on the issues, talk to another reference that you trust and ask him or her to address these points in their letter. A second reference can offer a "second opinion" and can even help build a stronger case for you by describing how you constructively handled issues with your advisor. As a person who has read several hundred letters of reference, I can honestly say that this strategy goes a long way in reducing the impact of a single reference's negative comments.

Another strategy is to simply rely on letters from references other than your advisor. While this will raise questions in the mind of a potential employer, the employer is more likely to be reassured if the letters you do provide are uniformly positive and explain the nature of the conflict between you and your advisor. If you do this correctly, you may come across a far more mature person than your peevish advisor!

Peter Fiske

Peter Fiske is a Ph.D. scientist and co-founder of RAPT Industries, a technology company in Fremont, California. He is the author of Put Your Science to Work and co-author, with Dr. Geoff Davis, of a blog (at on science policy, economics, and educational initiatives that affect science employment. Fiske lives with his wife and two daughters in Oakland, California, and is a frequent lecturer on the subject of career development for scientists.

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