I had lunch with a group of Miller Fellows, and the Director of the Miller Executive Committee, Professor Jasper Rine. We talked about a lot of things, but the discussion kept coming back to topics related to applying for research faculty positions, and the two body problem. Here's my summary of the key points:
Be forthright about the two-body problem.
Jasper has sat on several search committees, and it is his suggestion that, if there is a two-body problem (i.e., that two people are seeking academic, or professional positions, in the same physical location), it is best, as an applicant, to mention this up-front in the cover letter.
But, what if the search committee doesn't want to deal with two-body problem?
Search committees are concerned with finding the best applicant for the position and for their department, fullstop. The search committee will be interested in hiring you because of your academic record, the likelihood that you will collaborate well with the people in the department, and the expectation that you will be a productive faculty member. Search committees are also aware that many researchers will have partners who are also researchers. If the fact that you have a partner who will also require a position will negatively affect their decision to invite you for an interview, or to hire you, then the climate in that department will likely also reflect this. Or, more simply, if the department won't hire you simply because it might be difficult to find your partner a position, you probably don't want to go there anyway.
Okay, so they will hire me, even knowing about this other body. But why bring it up early?
I hadn't thought of this before, but Jasper pointed out that all departments have to work within a bureaucratic framework. What this means is, the sooner they know that they may have to work to find a position for two people, instead of one, the sooner they can get the paperwork rolling, the sooner they can seek out funding for an additional position, and the sooner they can contact other departments, and even other universities, about potential positions for your partner.
Sometimes the two-body "problem" can end up being an advantage.
Admittedly, the highest tier of Universities knows that they don't have to negotiate to get great people (and despite what you've heard about the benefits of multiple offers, some Institutions won't negotiate at all). But let's take a quarter-step back, and consider the excellent research institutions across the country that may not be located in the "ideal" locations (be it rural, or isolated with respect to other job opportunities, or in direct competition with the top-tier institutions, or very urban, who knows), or that have a higher teaching load, or, that may recruit fewer or no graduate students. These institutions understand that it is to their recruitment advantage to be able to offer two positions, and they can "steal" you away from another institution that is unwilling to negotiate these kinds of positions. Second, and more importantly, if you and your partner are both excellent applicants, it can be a direct advantage to the University to hire two highly-qualified candidates.
So, while the two-body problem is stressful, and requires cooperation from all sides, many institutions understand and value the benefits of dual-academic couples. (Please someone remind me of this in a few months.)