Benjamin Mako Hill has spent years studying the distinctive social dynamics and governance structures of collaborative websites, from open source software (GNU/Linux), wikis (Wikipedia), collaborative filtering (Reddit) and a range of social media. A noted hacker, activist, and computer science professor at the University of Washington, Hill has come to see that digital commons go through developmental stages, each with its own special needs. Fledging projects need to attract contributors by remaining open and welcoming, for example, while more established collaborative websites need to protect their shared code, curated information, and reputations from outside political and corporate players that attempt to capture their "epistemic legitimacy." More on the commons at www.Bollier.org. For more on the commons, go to www.Bollier.org.