Choosing a lab in which to carry out your PhD is admittedly one of the more important decisions you’ll make in your early scientific career. But it’s important to have some perspective. For starters, there’s no “best lab” or “best advisor” or “best project”. And there’s certainly no single “perfect lab” for you or anyone else. Rather, there are likely numerous labs that could serve your purposes well—labs that will provide you with rigorous training, a supportive environment, and a solid set of publications. Your task on entering graduate school is to weigh your options and position yourself so that you can hopefully choose between several worthy opportunities by the end of your rotations. But know that this will happen only if you hold up your end of the bargain. Even in a great lab, your success is largely up to you. And if you’re in a field where rotations aren’t standard procedure, know that you can still apply much of what’s discussed below prior to committing to a specific program or advisor. 

I’ll begin by outlining some of the main factors you’ll want to consider when first narrowing down your options. Some of these factors can be assessed, at least in part, prior to making any decisions about where you’ll rotate. In fact, you can do a good deal of homework before even setting foot on campus.  Other factors will become clear only after spending sufficient time working in a lab. In the end, you’ll do your best to make the most well-informed decision possible. But keep in mind that you’ll only be working on your PhD for about 5 years—probably a small fraction of your total career. An important 5 years? Absolutely. But just one step in a hopefully long and rewarding professional life.

Is the lab productive?

What could be more obvious? Perhaps you begin by searching the PI’s name on PubMed or Google Scholar or maybe check their lab’s website for a publication list. You read several of their recent papers—hopefully they have some— to see if they seem interesting. And yet, this central question can be legitimately confusing, even to experienced scientists! After all, it’s not just the number of publications. It’s also the type and quality of the publications. And what about the novelty, rigor, and depth of the studies, something that can be difficult for someone relatively new to assess? Moreover, although an average of five publications per year might sound great for a medium-sized lab, it sounds less impressive if the lab employs 20 personnel. And what if most of a lab’s papers are literature reviews or if the lab has played relatively minor supporting roles on most of its publications? Also, don’t forget that different subfields may have different expectations for what good productivity looks like. And then there’s new labs, ones that may have just started to gain traction but haven’t published yet. The truth is, productivity can be hard for even experts to accurately assess, as evidenced by occasional disagreements about this very issue among grant review panelists!

My intent here isn’t to make you throw your hands up in despair. It’s to make you aware of the issues so that you can begin to take them into account. But even if it’s impossible to precisely grade a lab’s productivity, it isn’t that hard to get the basic picture. Does the lab have very few or no publications over the past 5 years? Probably not a good sign. How about 12 primary research articles in good journals where the lab has played mostly leading roles? Sounds pretty good! So do your homework and then try to get additional perspectives from other members of the department such as graduate students or postdocs. The basic rule is that if a lab hasn’t been very productive in the recent past, then you’re unlikely to be very productive working there. Of course, it’s possible to defy the odds, and that includes being unproductive even if you’re working in a terrific lab! Even in the best of environments, it’s still up to you to make things happen.

Is the lab sufficiently funded?

It takes money to do science. It also takes money to pay your stipend and tuition and to send you to meetings. Where does that money come from? Well, if it’s an established lab, most of it likely comes from external grants, which can be difficult to obtain. This puts considerable pressure on lab heads, who are ultimately responsible for submitting grant applications, paying salaries, and keeping the lights on. You can sometimes get an idea about a lab’s funding situation by just looking at their website, as some faculty will list their main funding sources. In addition, you can search the databases of major funding agencies, such as the NIH or NSF (see below), who will list all the grants they’ve awarded. Of course, if it’s a new faculty member, they might not have their own grants yet but may still have ample funds to support you through a startup package provided by the university. So, what’s the best way to determine if a lab is likely to have sufficient funds to support you? Simple—ask the PI! It’s a perfectly reasonable question you can ask when you meet with them to discuss the possibility of doing a rotation. And if for some reason the professor is evasive or defensive, that probably tells you something you need to know. 

Still, one challenge that nearly all faculty face is the standard 3- to 5-year grant cycle. This can lead to uncertainties, because while we might have guaranteed funds right now, and possibly for the next few years, we often can’t say with certainty what our funding situation will be in 3–5 years, which is well within the time frame that you’ll be in the lab. And although that sounds scary, it generally works out OK for the student. If I were to try and predict whether a lab will be funded in the future, I’d look at their recent funding record along with their recent level of productivity. In fact, publications and funding are (in theory) closely connected and are part of a kind of positive-feedback loop. We need funding to do the work and publish papers. And we need those papers to convince agencies to give us more funding to continue our work. So, if a lab is currently funded and publishing well, that’s about as good a guarantee as you’re likely to get that they’ll be able to keep that going.

How have the lab’s previous graduate students fared?

Perhaps the best predictor for your future productivity and general satisfaction with a lab is the productivity and satisfaction of the lab’s previous trainees. For example, if a clear majority of the lab’s previous PhD students published several good first-author papers and have been able to move their careers in the direction of their choosing, that’s a great sign. You can figure this out by searching the internet and asking the PI, current lab members, and potentially other members of the department. In addition, lab websites will sometimes list alumni and where they are currently. Beware of labs where nearly all prior PhD students took 8 years to graduate and left with only one middling first-author paper. Another red flag is an inordinate number of students dropping out before earning their PhD. And while individual outcomes might say more about the qualities of individual students, clear patterns over time—for better or worse—should not be ignored. Here again, new faculty will not have a track record of prior students, which can make them more difficult to assess. And yet new faculty can be some of the most caring, energetic, and capable mentors. Often new faculty provide students with an opportunity to get in on the ground floor of an exciting new project, and their students usually receive extra attention. So, you’ll just have to weigh the various pros and cons and make a call. And remember that we were all new PI’s once and, fortunately, someone took a chance on us.

Is the lab a good fit for me?

The environment and ethos of a lab is determined by the PI in combination with the lab’s personnel. The PI generally sets the tone, but the people working there are what often give the lab it’s innate character. Sometimes you can get a reasonably accurate vibe about a lab prior to working there, but it often takes spending time in that environment and interacting with its personnel to know for sure. That’s one major benefit of doing rotations. By the end of 8 or 10 weeks, you should feel welcomed, accepted, and comfortable being yourself and perhaps even be valued. And you should be carefully observing how other lab members interact with each other. Do they ask each other for help or feedback or does everyone seem to go it alone? Is there a sense of comradery or are there cliques? What are the social expectations? Do they celebrate each other’s successes? How do people interact in lab meeting, journal club, by the water cooler, etc.? And while you can’t expect everyone to necessarily be best friends, there should be a clear sense that lab members are respectful and decent to each other. Also keep in mind that the PI is the only permanent member of the lab, and that the lab’s makeup is likely to change quite dramatically over the course of your studies, with senior people moving on and new people joining.

You should also have a clear idea about the PI’s expectations for students and their style of mentoring. Sometimes two perfectly reasonable people just don’t communicate well or see eye to eye. And if that’s you and your potential advisor, you’d probably be better off doing your PhD elsewhere. Maybe you’d prefer more (or less) direct oversight than the current students seem to be getting. Or maybe the mentor has an interaction style that you find challenging. Well, on the one hand, being challenged can be good and could indicate that this mentor cares about your learning. But if it’s not something you think you can handle on a daily basis, then it’s hard to see that situation working out well. These are all factors you’ll have to weigh along with everything else. But feeling sufficiently comfortable in a lab environment is crucial if you’re going to be spending the next 5 years there. And if the lab environment and ethos seem copacetic, great! You can add that lab to your list of potential options.

Am I excited about jumping on one of the available projects?

Note that this is a different question than, “Am I excited about the general area of science or the lab’s overarching goals?” To be sure, you should be able to answer the latter question affirmatively as well. But you also have to enjoy the types of experiments you’ll be routinely performing and take satisfaction in the day-to-day operations. Finding cures for cancer sounds great as an overall goal, but if your daily activities involve sacrificing rodents—and you really can’t handle doing that—then it doesn’t matter how excited you are about the long-term goals of the lab. And I’m not saying that you should necessarily be excited about every kind of experimental task you’ll need to perform. Most research projects involve some repetitive and possibly tedious aspects. But in general, the experimental techniques should interest you. A basic litmus test is to ask yourself whether you look forward to coming in most days just to see what new results you might get. Even though these are often very small pieces of the overall puzzle you’re trying to solve, carrying out such experiments effectively can still bring enjoyment and be satisfying.

Other factors and advice

• Your initial contact with potential rotation advisors should be through email, which is then followed up by in-person meetings. Be prepared. Nothing turns off a future mentor more than a prospective student having little or no idea about what their lab really does. No one expects you to be an expert, but you need to be reasonably well informed. Read through their website and look up a few recent published manuscripts. And take notes during your meeting. Also, if you can propose a relevant project using the lab’s abilities, the PI will know you’re really interested and thinking about the work. It doesn’t have to be particularly fleshed out or novel, but if you can think of a follow up for one of their publications, consider sharing that.
• Where do you see yourself in 10 years? If it’s in industry or maybe at a small teaching college, then certain types of projects and training experiences may better prepare you for those environments. That said, the single most important objective when getting a PhD is to receive rigorous scientific training, regardless of the specific subject area. Hopefully, you’ll be able to find a lab where you can acquire the types of skills you think will be most useful down the road and get excellent training at the same time. 
• Rotations represent a great opportunity to try out new areas of research, so take advantage of that. Just because you’ve had some experience working with system X as an undergraduate doesn’t mean that you’re obligated to continue along that path. Think about your prior research experience as a trek to a base camp on Mt. Everest. The trek got you into good physical shape and put you where you need to be. Now you’re going to climb the mountain, which is a separate thing entirely.
• Seek wide input from other students and postdocs in your program, but don’t put too much weight on any one opinion. Sure, if there’s a clear consensus about a particular lab, positive or negative, that’s clearly worth taking very seriously. But sometimes you’ll have to follow your own instincts based on your reading of people and your personal experiences.
• Not all PI’s will be equally up front about their expectations for students. It’s possible that the person who seemed a little intense or hard-core was just being more honest than the person who was trying to come across as cool and laid back. Again, talk to current students when possible and follow the data.
• Graduate program Directors can be excellent resources for information, such as which labs are looking to take students and how the program is run. But know that they might not be entirely comfortable weighing in on all the potential pros and cons of their fellow colleagues! Senior students and postdocs are less likely to have this kind of self-imposed filter but remember to take any individual opinion with a grain of salt.
• None of the above will matter if you don’t do good work during your rotation. Remember that while you’re evaluating the lab and the PI, they’re evaluating you! If you fail to make a good impression on the lab (typically both the PI and the lab personnel), then you’re unlikely to earn a spot with the group. Also, do a good job in all of your rotations, even if you realize after a few weeks that you’re probably not interested in returning to a particular lab. Trust me on this one.
• There are probably a dozen additional factors and pieces of advice that I’ve forgotten to include. Just know that much of your final decision about where to settle for your PhD will likely come down to small factors and personal preferences. Hopefully, if you follow the advice above and position yourself well, you’ll have multiple good options. And remember, if you’re doing four rotations, your goal is to deeply disappoint three labs with your final decision and make one lab extremely happy. If you accomplish that, you’ve done a great job.