Agile methods like XP, Scrum and DSDM have been advocating co-located teams in open plan offices now for 20 years. The idea being that since face-to-face communications are the fastest and most efficient, teams should be established to work this way whenever possible. Also, software projects, where agile methods started from, build intangible, often new and novel solutions to problems; as such there are lots of opportunities for miscommunication about how these new systems should look and work. Having people working together makes it easier to surface these misunderstandings, collectively troubleshoot problems and collaborate on new solutions.
However co-location is not always possible and open plan offices can suffer from “noise pollution” and frequent interruptions. The following infographic was created by a Voice Over Internet Protocol (VOIP) provider so probably has some selection bias, but importantly draws its findings from over a dozen respectable sources including articles from Bloomberg, The Guardian, the Wall Street Journal and Fortune.