Robin Dunbar observed that there was a correlation between the size of a primate’s brain, and the typical size of a social group. Extrapolating that out to humans, he arrived at a number of ~150 as the maximum number of strong relationship ties your brain can hold.
For instance, Gore-Tex discovered by trial and error, that if more than 150 employees were working together in one building, different social problems could occur. The company started building company buildings with a limit of 150 employees and only 150 parking spaces.
Source: Neocortex size as a constraint on group size in primates, Journal of Human Evolution, Robin Dunbar 1992
The Allen curve is a graphical representation that reveals the exponential drop in frequency of communication between engineers as the distance between them increases. It was discovered by Massachusetts Institute of Technology Professor Thomas J. Allen in the late 1970s. Several newer studies confirm the findings.
A team is a group of people who shares the same coffee machine.
Coffee Machine Rule
Within 50 meters, communications increase significantly, no matter the medium. Within 8 or 10 meters, people are most likely to form teams and collaborate.
A highly significant finding of Allen's was his identification of the key role of information gatekeepers, management usually is unable to identify.
A team should not be larger than sharing 2 pizzas.
2 Pizza Rule
Source: Managing the Flow of Technology, Thomas Allen, 1977
Knowledge workers usually collaborate on projects using their social networks to gather new ideas and feedback. What role play within-team networks and their members’ extended networks for the teams' problem solving abilities? This study shows that only the strongest ties in both networks have an effect on performance. Other factors of team performance such as technical competencies or the personalities of the team members were found to be non-significant.