We all know about advances in communications technologies – from email to Skype, from wikis to document sharing systems. And we know how they facilitate greater inter-institution and even international collaborations between researchers, providing an immediacy only dreamt of a generation ago. A number of studies have highlighted the impact of the large-scale collaborations and multi-disciplinary teams to which these advances have given rise, noting especially those that have emerged irrespective of geography. But proximity may be more important than these studies suggest. Last month, in PLoS One, Isaac Kohane and colleagues at Harvard Medical School and the Harvard-MIT Division of Health Sciences and Technology published a study in which they tested whether physical proximity was correlated with high-impact science at Harvard. They focused on life sciences articles published by Harvard investigators from 1998 to 2003, analyzing 35,000 articles in 2,000 journals by 200,000 authors. Each paper had at least one author from the university. To determine the physical location of the authors, the investigators – helped by a team of Harvard undergraduates – consulted floor plans and lists of building occupants provided by the human resource and facilities planning departments. Then they categorized the distances between them: by tens of meters (working in the same building), hundreds of meters (working on the same campus), or thousands of meters (collaborations across different campuses). Surprisingly, perhaps, given the focus on large-scale, international collaborations in recent years, they found that the impact of a paper – essentially, the number of times it has been cited – generally increased with the proximity of the first and last authors. The first author typically handles the lion’s share of the work in a study while the last author is usually the principal investigator. The two thus can be viewed as the key researchers in a given project. It’s not clear what’s behind these associations. It might be that physical proximity truly allows for better collaboration, the authors wrote, providing for higher quality research. It might also be that investigators prefer to keep potentially high impact projects in the family, as it were – in their own labs, or among a close-knit group of colleagues. Further work is needed, of course, to see if the findings are specific to institutions with organizational structures to that of Harvard, or to the biomedical sciences. Still, the authors of the study believe they should be taken into consideration when designing research centers, for example. “The question is, ultimately, which individuals do you want to bring together?” Kohane said. “If you want people to collaborate, these findings reinforce the need to create architectures and facilities that support frequent, physical interactions. Otherwise it’s really out of sight, out of mind.”