I recently was in a conversation about different effective group sizes. I brought up Falkvinge’s (founder of the Pirate Party) book / manual ‘Swarmwise’ as commenting heavily on it. Here’s a brief summary:

Falkvinge identifies three magic group sizes : 7, 30, 150

Seven People - Effective Working Group

This is a small group of deeply interdependent collaborators. The key tension is that each additional worker brings some productivity but adds N-1 new relationships which need to be maintained (the eighth member brings seven new ties to existing members). Falkvinge says the tradeoffs are unfavorable after seven members - too much time would be spent maintaining the group.

Thirty People - Loose Coordination Group

He refers to this size as an ‘extended family’ (side note - hunter-gatherers traveled in bands of 30-50). These are groups where you know everyone’s name plus a few other details. These groups are good for broad coordination, not deep collaboration. At more than 30 they form a bottle neck and should split in two.

150 People - Tribe Size

This comes from Dunbar’s number and Falkvinge cites it as the point at which informal groups lose their fun and efficiency. When he sees groups approaching this limit, he creates space for sub-swarms to emerge. Falkvinge also started with an empty global org chart with hundreds of positions and filled them as they expanded.

You can find the meat of group size analysis starting on page 51: http://falkvinge.net/files/2013/04/Swarmwise-2013-by-Rick-Falkvinge-v1.1-2013Sep01.pdf

The entire book is worth a read and is part memoir / part how-to manual. It’s a fascinating look at building decentralized organizations that maintain strong leadership. It pairs well with Graeber’s ‘The Democracy Project’ which chronicles the birth of OWS, a leaderless organization. Not surprising that the org with leaders was much more successful.